Hi,
If other icons which are pinned on taskbar don't have the issue, I think the issue is more related to Windows Live Messenger. Please contact Windows Live help center
below. You can click Ask a question to submit a request.
http://windowslivehelp.com/product.aspx?productid=2
From Windows 7 side, I suggest saving the following command as a bat file, then right click it and run as administrator to reset icon cache.
taskkill /F /IM explorer.exe
cd /d %userprofile%\AppData\Local
attrib -h IconCache.db
del IconCache.db
start explorer
Also, try to create a new user account, then pin the Windows Live
Messenger for a test.
Best Regards,
Niki
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