I recently a problem with a Lync user who was trying to share a Powerpoint presentation in an online meeting. When she tried to share the presentation, she received this error:

Some sharing features are unavailable due to server connectivity issues.

The immediate workaround was to share her desktop instead of the pptx file while I tried to figure out what was wrong.

Every other computer in the office could connect and share presentations without a problem, and it worked for this user on another computer. I decided that the problem must be with this one computer, but later it turned out that this was a distraction. The helpdesk completely uninstalled and reinstalled Lync, wiped cached data, rebuilt Outlook profiles, and more, but nothing made any difference. Then I learned that the user had just had a name change. Sometimes those name changes get a little mixed up, so I checked Exchange and Lync and, sure enough, found that the SIP address had been manually changed in Exchange to match the user’s new name, but Lync still showed the old SIP address. I wasn’t sure if simply changing the address in Lync would be sufficient, so I deleted the Lync account and created a new one using the correct SIP. The Lync address books on both of our computers hadn’t updated yet, so a meeting request was the easiest way to start a Lync session. Once the session was started, she was able to share a Powerpoint presentation with me via Lync with no errors.

I believe the problem was caused by a conflict between SIP addresses in Outlook and Lync. She was able to share the presentation on other computers because she didn’t have her email set up in Outlook. Once Lync had the same SIP has Outlook, it started working correctly. I wish Lync and Outlook wouldn’t share resources so intimately for just this reason, but at heart this was user error. Not on the part of the Lync user, but on the part of the person who performed the name change in Active Directory and Exchange without doing it in Lync also.