(A). The issue occurs when msxml4.dll doesn't get updated properly.
1. Remove the security update Kb954430 from Programs and features in Control Panel by clicking on View Installed Updates.
2. Delete the Msxml4.dll and Msxml4r.dll file from the location %SystemRoot%\System32 folder.
3. Download and Install the patch kb954430 manually from safe mode the link below:.
http://www.microsoft.com/downloads/details.aspx?FamilyId=96a4413c-5261-4f69-83d0-932c430abd14&displaylang=en(B). Boot in safe mode.
I would suggest you to boot the computer in safe mode and check if the you face similar issue
Steps to boot to safe mode:
1. Restart the computer.
2. Immediately after the screen goes blank for the first time, or after the BIOS post ends.
3. Start taping the F8 key repeatedly. The Windows Advanced Options menu appears.
(If the menu does not appear, restart the computer and try again. If the Keyboard has a F-Lock key, it may be necessary to press it first - QUICKLY before pressing the F8 Key. This will have to be done quickly before tapping the F8 key repeatedly.)
4. Select safe mode and press enter
5. Try booting to the desktop
Start your computer in safe mode
http://windowshelp.microsoft.com/Windows/en-US/Help/323ef48f-7b93-4079-a48a-5c58eec904a11033.mspxThen Install the updates in safe mode and check if it works.
Hope it helps
Thanks and regards
Dinesh-Microsoft Support
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