When using Outlook (or Windows generally), you may lose the ability to drag and drop items. For example, you may not be able to drag an email from the inbox into another folder.
The solution to this problem is (drum roll, please………..): press ESC.
You may need to press ESC more than once, but it seems to be a pretty reliable fix.
I don’t know all the combinations of Office and Windows that are affected by this problem, but I’ve had this problem with Windows 7 Enterprise 64 and Office Professional Plus 2010 32.
EDIT: Article has been updated to included Windows as a general culprit for this issue. Same fix works if you’re unable to drag and drop a file in a folder, etc.
EDIT EDIT: Added Lync to the title and tags based on a comment posted by “devnull”. Per the comment the same symptoms and solution apply. Thanks!