Yealink VC400 Administrator's Manual

Also see for VC120: Getting started Recovery guide Quick guide Administrator's guide User guide

Troubleshooting267If problems you encounter are not mentioned in this chapter, you can contact your distributoror Yealink FAE.General IssuesWhy is the display device black? Check whether the display device is connected properly to the VC400/VC120 codec. Check whether the system is in sleep mode. Press any key on the video conferencingphone or remote control to resume system operation. Check whether the display device is in sleep mode or is turned off. Press the power buttonon the remote control or on the display device. Check whether you have selected the correct video input source. You can try to switchvideo input source.Why doesn’t the display device display time and date correctly? If you have configured the system to obtain the time and date from the NTP serverautomatically, ensure that SNTP server and time zone are configured correctly in thesystem and whether the connection between the system and NTP server is workingproperly. If you have configured the system to obtain the time and date manually, ensure that youhave configured the time and date correctly.Why doesn’t the remote control work? Check whether the system is powered on. Check whether the positive and negative charges of the battery are connected correctly. Check whether the battery has sufficient power left. Check whether no special fluorescent or neon signs nearby.Why does the system fail to call the far site? Check whether the network of the near site is available. Check whether the network of the far site is available. Check whether the far site enables the DND feature. Check whether the accounts have been registered correctly, and the system uses theappropriate account to call the far site. Ensure that the number you are calling is correct. Check whether the far site rejects your call. Check whether the firewall blocks the inbound traffics from the other site.