Yealink VC800 - Page 279

Troubleshooting
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system and whether the connection between the system and NTP server is working
properly.
 If you have configured the system to obtain the time and date manually, ensure that you
have configured the time and date correctly.
 Check whether you hide the time. For more information, refer to Hiding Heading Time on
page 169.
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 the
appropriate 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.
 Check whether the far site has already up to maximum call-in limitation.
 If the near site is forced to use encryption, ensure that the far site enables encryption too.
For more information on call encryption, refer to Secure Real-Time Transport Protocol on
page 239 and H.235 on page 242.
 Ensure that the far site supports the same call protocol as the near site.
Why does the system fail to call the far site via IP address?
 Ensure that at least one call protocol is enabled on both sites. For more information, refer
to Configuring SIP Settings on page 102 and Configuring H.323 Settings on page 106.
 Ensure that the network is connected correctly.
 Ensure that the network is configured correctly. For more information, refer to Configuring
LAN Properties on page 24.
 Ping the IP address of the far site. Contact your system administrator if it fails. For more
information, refer to Using Diagnostic Methods on page 262.