Fix for error: Lync has both per-user and per-machine instances installed

Tuesday, May 10, 2011
You may see the error, "Lync has both per-user and per-machine instances installed. Click OK to remove the per-user installation."  The error occurs every time the Lync client is launched.

This is caused when a user has downloaded and installed the Lync Attendee User-Level Client, and then installs the Lync client.  This is bound to happen because the Lync Attendee client is freely available on the web (, but the Lync client is not. 

Remove the Lync Attendee and it fixes the problem.

1 comment:

  1. This makes sense, although I have scoured my client's computer and cannot find a copy of Lync Attendee or LiveMeeting.


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