User showed me this clock on the screen today - its modal but fixed on top. Anti-virus revealed nothing - and no shifty programs or services to my eye are running.
Hopefully AV deep scan will reveal something?
Download Process Explorer from http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx
& then use the 'Find Window's Process' Tool to find what process is running it. You can then google for the process to find if it might be a virus or a prank.
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