FAQ's and Troubleshooting




Q: How many extensions are supported on the CooVox series?
A: CooVox U20V2 support 30 extensions, U50V2 supports 100, U80 supports 200, U100V2 supports 500.

Q: How many simultaneous calls does the CooVox series support?
A: CooVox U20V2 supports 20 simultaneous calls, U50V2 supports 30 simultaneous calls, U80 supports 60 simultaneous calls, U100V2 supports 100 simultaneous calls.

Q: How many conference rooms can be created on the CooVox series?
A: CooVox U20V2 and U50V2 support 20 conference rooms, U80 and U100V2 support 36.

Q: How many simultaneous conference attendees does the CooVox series support?
A: CooVox U20V2 supports 15 simultaneous conference attendees, U50V2 supports 30, U80 supports 40, and U100V2 supports 80.

Q: How many call queues does the CooVox series support?
A: CooVox U20V2 and U50V2 support 20 call queues. CooVox U80 and U100V2 support 36 call queues.

Q: What's the maximum call recording storage time on the CooVox series?
A: CooVox U20V2: 36,000mins in GSM format; 4,000mins in WAV format.
  CooVox U50V2: 36,000mins in GSM format; 4,000mins in WAV format.
  CooVox U80: 1500hrs in GSM format; 150hrs in WAV format.
  CooVox U100V2: 75,000hrs in GSM format; 7,500hrs in WAV format.

Q: What's the maximum number of contacts that can be added to the CooVox V2 series phone book? What about LDAP server?
A: You can add up to 5,000 contacts into CooVox V2 series phone book, and the same amount for LDAP server, as LDAP server shares the phone book contacts.

Q: What's the maximum layer of IVR menus supported on the CooVox V2 series?
A: It’s unlimited you can have as many levels as you want.

Q: What's the maximum voicemail storage time on the CooVox V2 series?
A: The maximum voicemail storage time on CooVox U20V2 and U50V2 is 4,000mins, on CooVox U80 is 150hrs, and on U100V2 is 7,500hrs. 
Note: By default each user can have as many as 100 voicemail messages store in the CooVox IPPBX, old messages of 6 months ago will be deleted.

Q: Which IP phones are supported by CooVox series?
A: Actually all IP phones based on SIP and IAX protocols can work with CooVox V2 series as extensions. For example, CooFone Series IP Phones provided by ZYCOO, and also CISCO, Grandstream, Yealink, Polycom, Snom, Akuvox, Escene, Favil, HTek etc.

Q: Which soft phones are supported by CooVox V2 series?
A: Soft phones based on SIP and IAX protocols can work with CooVox V2 series. For example, 3CX, CooCall, Linphone, X-Lite, Zoiper etc. 

Q: Does the CooVox series support blacklist?
A: Yes, CooVox series supports blacklist.

Q: Does the CooVox series support video call? What about video conference?
A: Yes, CooVox series supports video calls but video conference is not supported.

Q: Does CooVox series support IP phone auto provisioning? Which phones are supported?
A: Yes, CooVox series supports IP phone auto provisioning. Phones of Zycoo, Grandstream, Yealink, Escene, AkuVox, Htek, Cisco, MOCET and Fanvil can be auto provisioned by CooVox V2 series.

Q: How can the extension users access the extension user portal?
A: “Web Manager” option needs to be enabled for the extension user to be able to access the extension user portal. Extension number and extension password are the login credentials need to be used.

Q: How do I create different user extensions other than 8xx?
A: Before you can create extensions in other number ranges you have to change the user extension range limit on Advanced->Options->Global Settings page.

Q: Can I add analog phones to CooVox V2 series as extensions? How?
A: If your CooVox V2 IPPBX has FXS ports equipped then you may connect analog phones to it as extensions. To assign an extension number to the analog phone you need to create a new extension number and select the FXS port number the phone is connected, once completed the analog extension is ready.

Q: How to register SIP/IAX extensions on IP phone and softphone?
A: To register SIP/IAX extensions you’ll need to “tell” the IP phone or softphone the IP address of the CooVox V2 IPPBX, the extension number and the password of that extension.

Q: How to register remote SIP/IAX extensions to CooVox series? Is it possible to link my CooVox IPPBX with another CooVox IPPBX from a remote office for free phone calls? How? 
A: Yes, you may have remote extensions and remote CooVox IPPBX integration, for more details please refer to the “Remote-extensions-and-remote-offices” guide.

Q: What are the supported formats of external USB drive that can be connected to CooVox series for call recording storage? What about the maximum volume?
A: The supported formats are FAT32, EXT2, EXT3 and EXT4. The maximum volume can be 1TB. Note: If you are using USB hard drive please use external power supply to drive it.

Q: Can I set the system prompts to my language instead of English?
A: Yes, you may change the system prompts to your language on System->Management page. The languages marked with * are built-in prompts, for other languages you have to download from ZYCOO web server, so please set valid IP for the CooVox IPPBX and click on Download button to download the language online.

Q: How do I make a 3-way conference call?
A: During a live phone call, press the “Conf” button on the IP phone to put the other party on hold, you dial the third parties number, when connected you press “Conf” button again to establish a 3-way conference call. 

Q: How do I start a dynamic conference?
A: During a live phone call, you press *0 to direct the other party to the first available conference room (by default 900, if 900 is in use, it would be 901) directly as an ordinary participant, you will be asked to input password to enter the conference, most probably you have to input the conference admin password, so once you have entered the conference you can invite third party numbers to participate in this conference.

Q: Can I backup and restore the CooVox series configurations? Can I restore backups from one CooVox model to other different CooVox models?
A: Yes, you may backup and restore configurations on CooVox series. But backups cannot be restored on different models, even if on the same model with different hardware configurations, they cannot share the backups. Please also be noted that the backup file contains sensitive information that may compromise your IP PBX system, please keep the downloaded backups confidential.

Q: Does the CooVox series support call recording? How does it work?
A: Yes, CooVox series supports call recording, there are 2 approaches to get phone calls recorded, auto call recording and one touch recording. Auto call recording feature needs the admin user to enable call recording feature for the extensions, one touch recording feature doesn’t require any additional settings, during a live phone call the extension user can just press *1 can get the conversation recorded.

Q: Does the CooVox series support Fax?
A: Yes, CooVox series supports traditional fax and virtual fax functionalities. For traditional fax functionality, if you have FXS port equipped on the CooVox IPPBX, you may connect a fax machine for sending and receiving faxes. For virtual fax functionality, fax machine is no longer needed, inbound faxes can be auto detected and saved in the IPPBX system or send to a user through Email, outbound faxes can be send through the extension user web portal. For more details of virtual fax functionality please click here.
Note: T.38 fax is temporarily not supported, but CooVox series support T.38 fax pass-through.

Q: How can I assign different dial permissions to the extensions on CooVox series?
A: Dial permissions are defined by dial plans used by the extensions. You can create several dial plans and in different dial plans you select different dial rules, and then you assign the dial plans to the extensions they will have different dial permissions.

Q: How can I pull the contacts from the CooVox series to the IP phones?
A: By using LDAP feature you may download phone book contacts from CooVox series IPPBX system to your IP phones. 

Q: How can I keep my CooVox series IPPBX secure? What kind of security precautions can be done?
A: Please refer to the “IP Phone System Security GuideV2” for detailed information.

Q: Should I always enable all System logging on the CooVox series?
A: It’s not recommended to enable system logging on the CooVox series as it will consume a lot of storage space. Only enable it when troubleshooting is needed.

Q: Can I use different ringtone for internal and external inbound calls?
A: Yes, there’s a feature named distinctive ringtone on CooVox V2 series that can distinguish inbound calls from internal and external callers. To distinguish external calls please set distinctive ringtone string on Inbound Routes->General page with format “;info=external” and then do necessary configurations on the IP phone (the IP phone should be able to support distinctive ringtone feature), please find more detailed information about this feature on the IP phone manual.

Q: Is there any way I can protect outbound calls with PIN codes?
A: Yes you may protect outbound calls by PIN codes. By creating a PIN set on Advanced->PIN Set page and applying the PIN set in a dial rule on Basic->Outbound Routes->Dial Rules page. Then if the extension user calling out using this specific dial rule one of the PIN codes will be required.

Q: Why I have changed the configurations but new settings didn’t take effect?
A: After you have made new configurations to CooVox series you have to click Activate Changes button on the top of the Web GUI to make it effective.

Q. What is DISA? How does it work?
A. DISA (Direct Inward System Access) is a mechanism available on some PBX’s that permits inbound calls to be answered and immediately presented with system dial tone. The caller is then able to dial a number that the PBX uses to decide how to forward the call. It is like the caller is able to dial twice – first to reach the PBX, then a second time to reach the final destination using the facilities of the PBX.

Q. What is Smart DID?
A. Smart DID is a feature that similar with last agent call routing. When a client missed the call from the agent of CooVox-V2 IPPBX system and he tries to ring back, Smart DID feature can route this call to the agent who had called him directly without going to the IVR.

Q. What is BLF? Does ZYCOO® IP PBX support it?
A. BLF (Busy Lamp Field), typically a collection of lights or indicators on a phone that indicate who is talking on other phones connected to the same PBX. Used by a receptionist or secretary to aid in routing incoming calls.
Yes, ZYCOO® IP PBX supports BLF by default, and you don’t have to configure on the IP PBX, just configure the BLF key on the IP phone.

Q. What is FXO lifeline to FXS? Does ZYCOO® IP PBX support this feature?
A. FXO lifeline to FXS is a feature that provided by our FXOS and 2FXOS modules, the FXO port can allow a PSTN call to ring/call the phone connected to the FXS port on the same module so it serves as a life line in case of power outage. If the mentioned modules are installed then that IP PBX can support this feature.

Q. What is call parking? How does it work?
A. Call parking is a feature of Asterisk that allows a user to put a call on hold at one extension and continue the conversation from any other extensions.
The number used to park a call on ZYCOO® IP PBX is 700, and the parking extensions are configured from 701 to 720. While in a conversation, press *2 or transfer button on the phone to initiate a transfer, then dial 700. Asterisk will announce the parking extension, most probably 701 or 702. Now hang up - the caller will be left on hold at the announced extension. Walk up to a different phone, dial the extension number announced- the conversation can be continued. If a caller has been parked for a longer time than the specified time limit then Asterisk will again ring the originally dialed extension.

Q: What is one number stations? How does it work?
A: One number stations feature can put several extension numbers in the same “group”, a main number can be selected from the members and when an incoming call is made to the main number, it will ring all the member extensions including the main number. Any extension within the group calling other extensions will display only the main number.

Q. What is PnP? How does it work?
A. PnP refers to plug and play of the IP phones, it's a more efficient way of provisioning the IP phones, just enable this feature and power on the IP phones then they can be provisioned from the IPPBX web GUI.

Q. What are the advantages of an IP PBX comparing to a legacy PBX?
A. See below:
No more phone wiring, it uses you LAN
Much easier of installation and management
Many more features but much cheaper than a legacy PBX
Remote extensions and branch offices, saving your long distance telephone expense
Significant cost savings using VoIP providers

Q. What are the advantages of an on premise IP PBX comparing to hosted/cloud PBX?
A. See below:
On premise IP PBX is cost-effective, it’s one time investment and there are no per user per month license fees.
On premise IP PBX is much more scalable, adding new users is just as simple as purchasing some more phones, but adding new users on a hosted/cloud PBX means more phones and more license fees per month.
On premise IP PBX is much more flexible, you can implement changes whenever you like to suit your business needs, but with hosted/cloud PBX you only have a handful options of customization.
With on premise IP PBX, the phone call quality is guaranteed, but with hosted/cloud PBX, call quality is a result of the Internet connection, also losing Internet means lose phone call services.



GUI and login issues
Q: I have the IPPBX connected in my LAN but I cannot open its Web GUI, what should I do?
A: 1). Please ensure the IP address of your PC is in the same network segment as the IPPBX system ( on WAN and on LAN).
2). Please check if there’s a collision of IP address, you may unplug the IPPBX system from your local network and find out if some other host is using the same IP address by PING.
3). Please ensure the IPPBX is completely started up, by checking the SYS led if it flashes once in 2 seconds which means it’s ready.
4). If SYS led never goes on it means a system failure, please contact support for help.

Q: While trying to open the IPPBX web GUI I got stuck by a security warning screen on the web browser, what should I do?
A: This is a certificate problem you can just click on “Continue to this website…” (IE) or “Advanced” and “Proceed to…” (Google Chrome) to continue.

Q: I got “Bad Request” on my browser while trying to open the IPPBX web GUI, what’s wrong?
A: Please try full URL:

Hardware related issues
Q: I have installed the module/modules into the module slots, but why the modules are not detected by the IPPBX system?
A: First of all please check if the module settings are correct, ensure module type of each slot is corresponding to the module has been installed on each slot. If settings are ok, please power off the IPPBX and unplug the telephony module and check if the protective oxide film has been removed or not. 

Q: I got SIM error on my GSM modules, what should I do?
A: First of all please verify the SIM card if it works on a mobile phone. If SIM works ok on a mobile phone, please check the GSM status after a reboot of the IPPBX. If a reboot makes no difference then please power off the IPPBX again and clear the SIM mating face with an eraser and insert it properly to try again.

Q: I tried to access the command lines through console port but failed, what could be wrong?
A: Please ensure you have specified correct COM port and baud rate should be 115200.

Q: Why I cannot get any files been stored in my USB drive?
A: Please ensure the USB disk file system is FAT32 or EXT2/3 format. If you are using a mobile HDD please use external power to drive the HDD.

Extension register issues
Q: I got error code 403 on my phone while registering the extension number, what can I do?
A: Error 403 occurs with wrong password or incompatible transport protocol, please ensure you have given correct password and the transport protocol on both the CooVox IPPBX system and the IP phone are the same.

Q: I got “Timeout” error while registering the extension number, what can I do to fix this?
A: Timeout means the IPPBX is unreachable or service unavailable, please check if you have specified exact IPPBX IP address or domain. 

Q: I cannot register IAX extensions on the IPPBX system, what could be wrong?
A: By default, IAX support has not been enabled on the IPPBX system, you have to create new extensions and manually enable IAX protocol then you may register IAX extensions to the IPPBX system.

Q: I failed to register remote IAX extensions, what could be wrong?
A: IAX protocol transports signaling and voice over a unique port 4569, please open port 4569 on your router/firewall so you may register remote IAX extensions.

Q: Why my remote extensions failed to register after upgrading to firmware version v2.1.5?
A: Please enable “Remote Extension” option for the remote extensions on Basic->Extensions page by clicking on edit button of the extensions. On firmware v2.1.5 remote extensions needs to be enabled manually, those extensions which are not enabled to be remote extension can only be used within your LAN.

Q: Sometimes my remote extension become “unreachable”, I can make calls but others cannot call me, what should I do?
A: This problem is caused by bad network condition, the extension is registered correctly but cannot be seen by the IPPBX in a specific time period and then considered unreachable from the IPPBX side. To resolve this problem please try improving your network condition and this problem can be resolved. If network cannot be improved please try to disable “Qualify” option of the extension on Basic->Extensions page by clicking on Edit button and find “Qualify” option then uncheck it.

Phone call issues
Q: We can’t receive caller ID on PSTN lines, what should be done to fix this?
A: Method 1: Please attach the PSTN line to an analog phone and call it from a mobile phone and see if you have caller ID or not, if it’s the same thing, please contact the telephone company for help.
Method 2: Please change caller ID detection parameters on Advanced->Options->Analog Settings page, try “Bell-US”, “DTMF” and “V23”, after each modification please confirm and reboot the IPPBX system then try inbound call again. 
Method 3: If both method 1 and 2 not working, please go to System->Troubleshooting->
Channel Monitor page, select a PSTN channel and click on Start button and then make an inbound call to this channel, after one of the extensions started to ring then you hangup and click on Stop button, at now a file will start to download, please send this file to our support team for help.

Q: Why I can call external numbers but can’t call internal extensions?
A: Please check your outbound dialing rules, you should not use dial patterns “.”, “X.” or “XX.”, the length of the pattern must be longer than the length of the extensions (Default extension length is 3 digits). For example, correct dial patterns should be “XXX.”, “9XX.”, “NZX.”, etc.

Q: Sometimes I got disconnected on PSTN calls, how can I fix this?
A: Please try to change “Busy Count” value from 3 to 6 or you can try disable “Busy Detection” on the PSTN trunk.

Q: The voice quality is not good on the PSTN lines, what can I do?
A: Please activate “Denoise” on Advanced->Options->Analog Settings page.

Q: If I was on a phone call, other phone calls can still come in, what I can do to stop others from calling me when I’m on a live call?
A: Please disable “Call Waiting” on the IP phone. For more information please refer to the IP phone user manual.

Q: My phone does not accept any password or keypresses so I cannot check voicemail, join in a conference or do a call transfer, what should I do to fix this? 
A: Please check the DTMF method of the IP phone, ensure it’s the same as IPPBX, default value of CooVox IPPBX is RFC2833.

Q: Why I can make phone calls but others cannot call me?
A: Maybe you have activated call transfer or DND (Do Not Disturb). Dial *075 to deactivate DND, dial *071 to deactivate forward all, dial *072 to deactivate forward on busy or dial *073 to deactivate forward on no answer, after this please try again.

Q: While calling from the PSTN lines, I can hear the other party but the other party cannot hear my voice, what should be done to fix this issue?
A: Please reboot the IPPBX and try again, if still the same, please set “Answer on Polarity Switch” option to “No” on the PSTN trunk configuration.

Q: I’m using remote extensions and found out the voice quality is not so good, what should be done? 
A: Please force your phone with G729 codec and try to enable SIP buffer.

Q: I’m having one-way audio on my remote extensions, what should be done to resolve this problem?
A: Please enable “NAT” option on Basic->Extensions page by clicking on Edit button of the remote extension and find “NAT” option and enable it.

Trunk related issues
Q: My E1 PRI trunk status is showing “Connected” but in red alarm, what should I do to fix this?
A: Please first make sure the PRI line is activated by the service provider, if the line has been activated please power off the IPPBX and check the E1 module jumpers. If on U50V1, make sure the Jumpers on Master position, if U100, U80 and U100V2, make sure they are on Slave position.

Q: My E1 PRI trunk status is showing “Disconnected” but no alarm, what should I do to fix this?
A: Please first verify the E1 line is working, if the problem persists please check with the service provider if CRC4 has been applied or not, then on the module settings page please make necessary changes of the CRC4 parameter.

Q: My SIP trunk registered correctly to the service provider and I can receive inbound calls from the SIP trunk but I cannot make outbound calls from it, what could possibly be wrong?
A: The problem is most probably caused by the outbound calls cannot be authenticated by the service provider, please go to Basic->Trunks page and edit the SIP trunk, in the “Advanced Options” section please fill in the “From User” field with your SIP trunk username. 

Q: When I try to make phone calls from the SIP trunk I always got busy signal and error code 5XX on my IP phone screen, what could be wrong?
A: The problem is most probably from the service provider side, you may check you trunk balance and contact the service provider for help.

Q: Why I can make outbound phone calls through my SIP trunk but cannot receive any inbound calls from it?
A: Please ensure the sip trunk context is “default”.

Logs and files issue
Q: Why I cannot find any recent call logs or call recordings?
A: Maybe your IPPBX system is running with an inaccurate system time, please change its time settings and the new records can be found. About the old records you have to search from date Jan 1st 2010.

Q: Do I have to always turn on system logging? If not, when should it be turned on and what kind logging should be turned on?
A: It’s not recommended that you always turn on the system logging, only when the IPPBX system is running into exceptions you can turn on system logging for troubleshooting. About which kind of logging should be turned on it depends on what the problem you want to troubleshoot:
Enable System Log: Turn it on if you suspect the module malfunction or the operating system malfunction.
Enable PBX Log: If there’s IP phone register or VoIP trunk register problem please turn it on.
Enable PBX Debug Log: If there’s phone call problem you can turn it on.
Enable Access Log: Turn it on and you’ll be able to see all web and ssh login attempts and where the login is originated from. 

Maintenance issues
Q: After upgrading the firmware web GUI does not updating new features and the page display is abnormal, what should be done to fix this issue? 
A: It is caused by browser cache or compatibility problem, please clear the web browser cache or change a browser and try again.

Q: Why I always got error notice while trying to upload new firmware to upgrade?
A: ZYCOO IPPBX firmware can be downloaded from the website, and you will get a .rar or .zip compressed file, please un-compress the file you have downloaded then upload the “uImagexxx” file to upgrade, please also ensure that you have downloaded corresponding firmware for your IPPBX model, different model of IPPBX can only be upgraded by its own firmware. 
Notice: Firmware for CooVox V2 cannot be used by CooVox V1 and vice versa .

Q: Why I cannot restore backup file?
A: Maybe you have changed the file name of the backup file.
Maybe you were trying to upload backup from another different IPPBX.

Q: When and how should I reset the IPPBX by the Reset button?
A: On CooVox U20V2 and U50V2 there’s a Reset button on the rear panel that can be used to reset the IPPBX system to factory defaults. When the system is malfunction or you have difficulty to access the Web GUI you may reset by the Reset button. Please be noted that if you reset because of losing Web admin password, after resetting please do not use backup file to restore configurations, as the backup contains old password that you’ve forgotten.
Reset Configurations:
On system running mode (sys led blinking), you can hold the RST button for 6-8 seconds till SYS led goes off, then release, system will reboot and reset, reset will take around 2mintues.
Reset whole system (it will clean all configuration and data):
First turn off the device, hold RST button and turn on the device, release the RST button until the sys led is on, system will rebuild completely new file system, the whole process will take abround 8 minutes. After this you’ll lose ALL kinds of data on the IPPBX system.

Q: I cannot access the CooVox IPPBX AMI, what should be done?
Step1. Please grant the AMI port access on Security->Firewall page, in the “Common Rules” section there’s a default rule named “Refuse AMI”, please edit this rule and change action “Drop” to ”Accept”.
Step2. On System->Management page, please activate operator user.
After this you may use user name operator and the randomly generated password to access the CooVox IPPBX AMI through port 5038.

Q: Why I cannot sign in CooBill?
A: You have to use extension number or operator user to login in. If extension number, please ensure “Web Manager” option is enabled on extension configuration page. If operator, please ensure operator user is activated on System->Management page.

Q: How do I use CooCall to register an extension to my IPPBX? 
A: CooCall on iPhone uses TCP protocol while on Android phones it uses UDP protocol, please make sure you select appropriate protocol for the extensions according to the clients they are going to register from.

Q: Music quality is not good when calling in from the PSTN trunks, SIP trunk is ok, how can fix this problem?
A: Please try replace the MP3 music files with 128kbps bit rate files.