My Dad has a Dell with XP Home and he had to Repair the OS because of issues of files he may have deleted by accident.
The fix went well with help from Dell, and everything worked except I noticed he kept getting a yellow shield stating that there were updates downloaded and ready to install.
O.K., I went to the icon and chose all updates (91) to be installed.
It started the process (Updates were already downloaded) and then all of a sudden it stopped and said that all updates failed. In my haste I forgot to write the code error but it was something like Xoooe5 or something like that.
I did try to do a single update install also with the same result.
Should something stop the updates?
The system has SP2, and it is a legal version. (I did verify it)
Any ideas??

Repairing XP often results in this problem. See /t202817-XP_Repair_Woes.html and http://support.microsoft.com/?kbid=943144

To solve the problem the wups2.dll file needs to be registered (taken from the MS page above).

To register the Wups2.dll file in Windows, follow these steps:

1. Stop the Automatic Updates service. To do this, follow these steps:

a. Click Start, click Run, type cmd, and then click OK.

b. At the command prompt, type the following command, and then press ENTER:
net stop wuauserv

2. Register the Wups2.dll file. To do this, follow these steps:

a. At the command prompt, type the following command, and then press ENTER:
regsvr32 %windir%\system32\wups2.dll
Note For a computer that is running Windows XP Professional x64 Edition, type the following command, and then press ENTER:
regsvr32 %windir%\syswow64\wups2.dll

b. Click OK on each verification message that you receive.

3. Start the Automatic Updates service. To do this, type the following command at the command prompt, and then press ENTER:
net start wuauserv

4. Exit the command prompt. To do this type exit, and then press ENTER.

Thanks for your quick reply.
I did get a answer from a MS Newsgroup from a MS Tech.
Seems there was an issue with repairing XP WITH the disc.
The computer is at my Dad's and I will fix it this week.
The answer is clear as day in the KB.
Thanks again for your answer.....
Sometimes we look too hard at something and miss the obvious answers...
I will let you know the progress of this issue....

Thanks to all of you who responded with solutions....

The solution from another forum was to re-register some .dll files
After rebooting I was able to install all the updates without a hitch.
There were over 80 updates, then a series of 10, 5 ,3 ,3 after the updates were installed. (Mostly follow-up patches for Net Framework 1, 2 & 3 and other updates).

Those files were:

regsvr32 wuapi.dll
regsvr32 wuaueng.dll
regsvr32 atl.dll
regsvr32 wucltui.dll
regsvr32 wups.dll
regsvr32 wuaueng1.dll
regsvr32 wucltui.dll
regsvr32 wuweb.dll
regsvr32 wups2.dll
regsvr32 msxml.dll
regsvr32 msxml3.dll
regsvr32 msxml2.dll
regsvr32 qmgr.dll
regsvr32 qmgrprxy.dll

Special Thanks to simpswr from Tech Support Forums