Windows 7: Windows Update fails in Update Check. Error code C80003FA.

Hello,

I recieve error C80003FA whenever I do a Windows Update run. It doesn't get past the stage of checking for updates.

I've tried several fixes including:
- Waiting 15 minutes and running Windows Update again.
- Letting Windows Update run on its own schedule.
- SFC /Scannow
- Renaming the Catroot2 Folder.
- Running 3 different Fixit tools.
- Clean windows install.

After each and every one of those fixes I've tried windows update and I still get error C80003FA.

SFC Scannow has previously said no errors, but the last run through it said there were unfixable errors. I've got the log, though for brevity's sake I will keep it until someone asks for it.

Any ideas?

Thanks.

Clean windows install doesn't fix it? You must be blocked, maybe your firewall???

C80003FA - this appears to be a 'ReadVerify failure' - which implies corruption of data in RAM or in transit.
I would suggest testing RAM using MemTest86+ (www.memtest.org) - run it for a few hours and see whether it brings anything to light.

Thanks for the replies. No memory errors here. I did get a bunch of updates installed on an auto-update last night. It was miraculous. I tried to check for updates again today, and got the same error as always. I'm thinking this is somehow firewall related. And mostly likely my modem-router. Thinking back, I previously had no issues with the router I am using, but when I signed up with a new ISP they provided me with a wireless modem-router (CISCO DPC 3825) and I had switched to Windows 7 after that. Since then I've had issues.

I've tried looking up portfowarding for Windows services, but I couldn't find anything. Any suggestions?

Open Windows Update
Click on Change Settings
Select 'Never Update...'
Click OK
exit Windows Update
Now open Windows update again
Click on Change Settings
Select 'Update automatically'
Click OK
exit Windows Update
Open Windows Update, and do a manual Check for Updates.

After trying that I still get the same error.

Please run another SFC /SCANNOW, then copy the CBS.log file to your desktop, zip it, and attach it to your response.

Here it is!

A small suggestion. Make sure I.E. is your default browser and also make sure their is no browser accelerators being used.

That SFC found nothing amiss that I can see, although it did a fair amount of tidying up.
Try running this Fixit...
http://go.microsoft.com/?linkid=9665683

If it doesn't sort it, downlaod and run the CheckSUR tool, then attach the (zipped) CheckSUR.log and .persist.log files it creates
System Update Readiness Tool fixes Windows Update errors in Windows 7, Windows Vista, Windows Server 2008 R2, and Windows Server 2008