I had the same problem a few months ago. Below is what I found searching. What worked for me was re-registering the DLLs (first section below). But I saved a copy of the entire thread as a reference..........
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Go here and see if it works
http://www.microsoft.com/genuine/
fix any issues, then validate it.
If it still doesn't work try this
Re-register the Windows Update DLL with the commands below
Click Start, click Run, type cmd, and then click OK.
Type the following commands. Press ENTER after each command.
regsvr32 wuapi.dll
regsvr32 wuaueng.dll
regsvr32 wuaueng1.dll
regsvr32 wucltui.dll
regsvr32 wups.dll
regsvr32 wups2.dll
regsvr32 wuweb.dll
Attempt to run Windows Update
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Try this
by tallin - 12/27/07 7:41 PM
In reply to: Problem - Windows XP updates will downlaod but not install by Greatwazoo42
I have posted this so many times on this site so here it is again and I hope it helps you out.
Post back if you need more information as I have other help to give, but we will start with this.
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Step 1:
Verify that your computer's date and time are accurate and that Internet Explorer language option is not empty.
To check the language setting in Internet Explorer:
1. Click "Tools" and then choose "Internet Options"
2. Click the lanuage button
3. Make sure at least one language is listed in the "Language Options" dialog.
When checking your date (including the year) and time, also check the Internet Time and Time Zone. Double click on the date/time in the notification/system tray area (near the clock) select Internet Time Tab and then select update now. If it's not already checked, check automatically synchronize with an internet Time Server - WinXP.
Step 2:
Also check these settings:
1. Tools>Internet Options> Advanced
2. Scroll down to the Security Settings.
3. Make sure that the two boxes are checked that say "Enable SSL 2" or "Enable SSL 3".
4. Uncheck "Check for server certificate revocation".
Step 3:
Also delete Temporary Internet Files
1. Tools>Internet Options >General
2. Under Temporary Internet files, click Delete Files, Clck OK
Step 4:
1. Tools> Internet Options > Security
Click Trusted sites, click Default level.
Click the sites button and clear the checkbox "Require server verification"
(http
for all sites in this zone."
Now add the following:
http://*.windowsupdate.microsoft.com
https://*.windowsupdate.microsoft.com
http://download.windowsupdate.com
If required, reboot and try Windows Update again. If still no success, have a look at the following links for more clues.
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Further information:
You have mentioned error code notifications, but this information is valuable just the same if you ever were to bump into these problems.
Error 0x800A138F
http://www3.telus.net/dandemar/0x800a138f.htm
The aim here is to help you solve this 0x800A138F problem and have you updating your Windows XP Professional or Home Edition computer as soon as possible.
http://updatexp.com/0x800A138F
Windows Update has encountered an error and cannot display the requested page.
http://www.petri.co.il/wu_problems_800a138f.htm
0x800A138F
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Make sure you haven't got anything blocking Windows Update like
Nortons,
Zonealarm etc
Also make sure you don't have a Web Accelerator working in the backgound such as
Net Zero
HiSpeed
Speedband etc
Clear out your temporary internet cache
Try a reboot and then try WU again.
Are there any specific error codes that you do see?
At what point does it continue when checking for the latest software, or when checking for updates?
Still no joy, then try Renaming the SoftwareDistribution folder
Click START, Choose Run
In the Run box, type "services.msc. " (without the quotes)
Click OK
Right click the Automatic Updates service,
Click stop.
Stopping the service will take a moment.
Rename the "SoftwareDistribution" folder :
a. Click Start, click Run, type "%systemroot%" (without the quotes" and then click OK.
b. Right click the SoftwareDistribution folder, and then click Rename
c. Type SoftwareDistribution.old, and then press ENTER to rename this folder.
Click START
Choose Run
In the Run box, type "services.msc." without the quotes"
Click OK
Right -click the Automatic Updates service
Click Start.
Starting the service will take a moment.
Reboot if appropriate and try WU again.
Note when you rename the SoftwareDistribution folder - you will loose your history but not important.