In Windows 7 or Windows Server 2008 R2-based computer, when the system is configured to automatically log on when user starts the computer, any customizations that user made to the Taskbar may be lost, and the Taskbar is reset to its default settings or configuration.
According to Microsoft’s KB979155, the problem of losing customizations on Taskbar on Windows 7 or Windows Server 2008 R2 is caused by a race condition between Windows Explorer and Taskhost.exe. No more specific information is available though, but a hotfix has been made available to fix and resolve the Taskbar resets to default issue for user accounts that have been configured to automatically log on.
However, it is intended to correct only the problem that is described above. So the hotfix should be applied only to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next service pack that contains this hotfix.
To download the KB979155 hotfix, users have to contact Microsoft Customer Support Services to obtain the hotfix, through http://support.microsoft.com/hotfix/KBHotfix.aspx?kbnum=979155. However, interested users can also download the hotfix via the download links below. The hotfix supports all language versions.
i386 (32-bit or x86): Windows6.1-KB979155-x86.msu
x64 (64-bit): Windows6.1-KB979155-x64.msu
ia64: Windows6.1-KB979155-ia64.msu
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