Windows 10 Pro 64bit Version 1607 build 14393.187
Run "Quick Assist" as Administrator ( or user account, makes no difference)
Login with Microsoft outlook.com account
Quick Assist window clears and for further information is displayed
Window is not frozen, can minimized, restored or moved, click mouse anywhere in window, no result

Click image for larger version. 

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Same PC can run Quick Assist, Get assistance, enter code from sending PC, Submit, screen sharing works as expected.

Help Please?
Thanks in Advance