Call transfer to user doesn't work

Not able to transfer calls to one user

 

Recently I came across this very weird issue whereby any users in lync 2010 environment can not transfer calls to particular users ( i.e if they transfer it by searching name in lync client ) however, if they transfer calls by that user’s extension number then they could successfully transfer the calls.

In nutshell, if they transfer call to user’s SIP uri then call will fail and if they transfer it to his extension then call will connect.

After obtaining debug logs on Lync FE server, I found that Lync was trying to transfer call to  “ 0867588” number because of refer message. ( As this site had media bypass enable )

So main issue was that user’s sip uri : 0867588@domain.com

If in your environment any usre’s SIP URI is number and if you have media bypass enable then any other user won’t be able to transfer external calls to that particular user ( who has number in SIP URI) because of the refer message only gives number to front end server and then instead of trying to send call to sip uri , lync will try calling that number and call will fail.