PC Windows XP on automatic updates.
Icon on task bar at every startup 'Click to install update.
Downloads and apparently installs update but seconds later task bar icon re-appears.
Belarc Advisor shows ' 1 missing update ' after each attempt to update verifying that update has not taken place.
Microsoft statistics show update as downloaded and installed ( approx. 20 times).
Update in question is " Microsoft Visual C++ 2005 Redistributable KB2538242 ".
ADD/Remove programmes list on PC shows " Microsoft Visual C++2005 Redistributable KB2467175 (downloaded 25/4/2011).
I have tried reinstalling 'Windows installer' in the hope that this would correct the problem but it continues and I would be grateful for any suggestions.

It sounds as if your windows C++ itself is bugged or your virus protection is preventing windows from patching correctly. You can first try turning your virus protection off and doing your update to see if it completes successfully**Do not forget to turn protection back on when done!**, if not then follow steps below.

Step 1: Open up your control panel and go to add/remove programs(vista/7 is programs and features).

Step 2: select Microsoft Visual C++ and remove it. You may have to go into windows features tab or look for a check box that allows you to show Windows components depending on how you have your windows set up. If you don't use that feature simply remove and leave it that way. If you do use it go to step 3. If you don't use it go to step 4

Step 3: Reinstall the feature. You will need your windows disk to do this. A manufactures windows disk does NOT always work. If you do not have your disk, or your manufactures disk will not work you can find the C++ feature as a download on windows website here:http://www.microsoft.com/download/en/details.aspx?id=5555

Step 4:Run windows update again. This should either A(if removed) not find any updates or B(if reinstalled) find and patch your program

Grateful for your effort to help, DarkVision.Followed your instructions.
Have tried to remove Microsoft Visual C++ without success.Get message saying unavailable 'disk' is needed.Only disk I have is Master Disk created after purchse of PC.Tried this also without success.
Even in Safe Mode am unable to install download from windows website.
Have contacted Microsoft Fix It center and await their assistance.
Thanks.

Thought it appropriate to let all know (all who tried to help and those who may have the same problem in future).
While awaiting assistance from Fix it Center,I managed to resolve the problem myself as follows:- download
'Microsoft Visual C++ 2005' from 'download.cnet.com'.
Then manually download the update from Microsoft.
You may have to install the update a second time.
Then check that there are no outstanding updates.Done!

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