Why? Because they are blocking changes like that. Could be other reasons such as trojan infections.
Bob
Before including the quoted popup messages, I do want to say that I accidentally corrupted Windows XPSP3, primarily Internet Explorer 8 which is now non-functional along with the Windows Update function button. This may be the cause of the problem given below. It is my understanding that using Windows XP Repair can cause more problems than it solves. Is this issue something that is so critical that I should give it immediate attention or can it wait for a while? Some time in the very near future (on a rainy day) I will be installing a new hard drive and reinstalling Windows XP. Other than the IE8 and update problem everything else seems to be working fine. Your thoughts please.
"Choose update to install
Update Title
Cumulative Security Update for Internet Explorer 8 for Windows XP (KB2722913)
Security Update for windows XP (KB2723135)
Security Update for Windows XP (KB2731847)
The updates are being installed
Installation status:
Initializing installation... done!
Installing Cumulative Security Update for Internet Explorer 8 Windows XP (KB 2722913) (update 1 of 3)... failed!
Installing Security Update for Windows XP (KB2723135) (update 2 of 3)...failed!
Installing Security Update for Windows XP (KB2731847) (update 3 of 3)...failed!
Some updates could not be installed
The following updates were not installed:
Cumulative Security Update for Internet Explorer 8 for Windows XP (KB2722913)
Security Update for windows XP (KB2723135)
Security Update for Windows XP (KB2731847)"

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