Q850 error codes
Yealink devices give Q850 error codes on the screen, e.g. Q.850; cause=17 'user busy'.
This sometimes causes confusion.
More information: http://support.yealink.com/faq/faqInfo?id=567
If the other party is busy, the call will be disconnected at VOIP. If you want a busy tone generated anyway, you can do this by activating the function in the telephones.
We have a config file that adjuts all these settings; if you need is please ask.
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