Hello.

Some of users are having issues due to the unsupported configuration.

Issue:

Availability and Calendar are not working properly due to their configuration.  For example, their Primary SMTP address is set to John.Doe@CompanyB.com yet their SIP address is John.Doe@CompanyA.com

I have already advised to change to John.Doe@companyA.com and this would resolve the issue. But I am asking question if there's a work around.

Workaround I heard:

I was advised to add "SIP:John.Doe@company.com" to SMTP area.   but not sure how this can be done.

Please advise if someone can help

Alex

Typically it's better to have the SMTP and SIP addresses match, but you can try setting the DisableEmailComparisonCheck parameter in Set-CsClientPolicy. This should then pull Calendar/Contact information straight out of Outlook (irrespective of the SMTP address), rather than use SMTP to verify Outlook and Lync are running as the same account.

See more here: https://technet.microsoft.com/en-us/library/gg398300%28v=ocs.15%29.aspx

Also take a look at this article, to see if it can be of help: http://sparesomeexchange.com/exchange-2010-and-lync-2010-integration-when-sip-address-does-not-match-primary-smtp-address/