

I am not sure how much of this was “just to be sure”. This consisted of backing up my email into a new PST-file (not needed), deleting everything under C:\Users\mywindowsuser\AppData\Local\Microsoft\Office\15.0\Lync and changing the username part-by-part first the last part from domain.no to, then the first part, then the last part back again – and logging in to between the steps, checking that my Lync settings was being propagated.

While Microsoft told me it was possible to fix this by changing my Lync logon from primary email to username, the best solution for me was to change my username to match my primary email address.
#Microsoft lync messenger password
Pidgin required that my username be my Office 365 username (or else it would give password error), but it would give the elusive SIP URI mismatch error if I put anything else than blank or my username in the logon field. Possibly because we were early adopters of BPOS (previous version of Office 365), possibly because my first-time signin on Lync was using my primary email, possibly because of something else entirely, Lync signed in with my primary email while Outlook and everything else signed in with my username. The problem was due to my primary email being different from my account user name. I am duly impressed both by Microsoft and the-man-whose-name-contains-a-lot-of-a’s in this case. He went above and beyond on my support request, consulted superiors, spent several hours with me on the phone while we worked together on debugging and fixing this – and this on a problem and client (Pidgin) that Microsoft does not even support! The great interwebs did not have a lot of information, but the case was eventually solved by heroic effort from Microsoft support engineer Sankaranarayanan (v-9sak). My environment was Pidgin 2.10.7 and SIPE 1.15.0 on Win8 connecting to Office 365 (no local AD).

The Pidgin GUI kept saying “Web ticket request to webdir0e- :443/ CertProv/ CertProvisioningService.svc failed” while the debug log from running pidgin –debug ended with an XML containing “Web ticket request error – SIP URI mismatch” – after confirming username and password to be ok. I had been trying to get the open source instant messenger client Pidgin to connect to Lync using SIPE.
