Microsoft has released the new KB975496 update addressing the issue while using BitLocker for system drives.If your Windows 7 PC stops responding during shutdown if BitLocker is enabled on the system drive.
Initially this update was released for Lenovo ThinkPad W510 where the issue was first noticed.Now Microsoft has decided to release this update as “recommended” update type to all x86 Windows 7 users in April 2010.
KB975496 details:
Update for Windows 7 (KB975496)
Download size: 121 KB
File name: Windows6.1-KB975496-v2-x86.msu
published: April 26, 2010
You may need to restart your computer for this update to take effect.
Update type: Recommended
More information:
http://support.microsoft.com/kb/975496
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Direct Download Link: KB975496-v2-x86.msu (Without validation)