Cannot Install SP2? Stuck on "Checking Product Key"

I recently had a Dell D505 laptop in the workshop that refused to install Service Pack 2. Each time, it just stopped on "Checking Product Key"

The product key was correct but it could get no further - the Update process would then use 100% of the CPU and had to be closed manually.

After searching the net, I found a few other users with the same problem and generally the solution was to reinstall Windows with SP2 slipstreamed into it already. Since this was already a fresh install after a hard disk failure, I was not keen on this plan.

Then I found the solution (thanks Ste123) on a Microsoft forum of all places and here it is. Naturally, use it at your own risk.

1) Open a CMD prompt
2) Then type cd /d %windir%\inf
3) Then type ren oem*.inf oem*.old
4) Then type ren oem*.pnf oem*.old1
5) Then find the file by name INFCACHE.1 and remove it from the inf directory
6) Close all windows and reboot the computer to safe mode and
start the installation of SP2 and it should go fine



Awesome fix, worked great, but do you have any idea why it happens in the first place? also where did you get the info?

You're welcome, however the person who deserves the thanks is a guy called ste123 and I found the fix here.

Hi Chris, I'm from Portugal and actually i have same problem with a friend's Fujitsu notebook that got his HD crashed. I'm gratefull to you because your post was the first that i found when i search on google. Of course, i'll thanks to that guy too. Regards, Rui

Great Fix, Also works for Windows Server 2003 to install SP1. Didn't need to restart in safemode. Just rename the files and delete the infcache.1 and start the SP install

one question where is INFCACHE.1 i can open it but i dont know where it is located...where do u find the inf directory


sweet, works fine dude. Thanks a lot

In your case you need to purchase a valid copy of XP or use a non Microsoft open source desktop package like Ubuntu

Thank you so much. This worked beautifully!

c:\windows\inf (its a hidden folder)

Hi Chris, Worked great!! Thanks so much

Dustin Here from Hawaii
I have a sony vgn-a190 and this worked great,
thanks soo much!!!

Saved me a lot of time and grief thanks STE123.

Thanks for posting this, it worked perfectly.

Worked a treat! Chairs fella!

Cool stuff, the fix works a treat for me. Straight forward and one time. I am adding this comment just after the intallation finished. Danke Bethel Chika B C

Finaly I found something that worked, thanks very very much. I could have saved myself a day of work and a call to the Microsoft helpdesk to get my Windows activated again. Ah well, nothing better than a good solution after frustrating things. :) Tjerk, the Netherlands.

I don't think booting on safe mode is necessary, coz i just booted up normally, updated to SP2 and it was successful. :] other than that, this is a big help

Thanks Chris! You saved me possibly countless hours of frustration with this one! Brown star ahoy!

Thank you!!! That got me past the product key problem, now if I can just get it past the ntdll.ll error I should have it made :o)

I just want to thank you for fixing my issue. I did what you said and it ran like a charm. Yuo Da Man!!!

Did al that was asked, typed all commands, got to folder easily But unable to find C:\WINDOWS\inf\infcache.1 !!!!

Worked for me. Thanks for the help.

How exactly do you find and remove the INFCACHE.1 file from the inf directory? Also, when rebooting in safe mode, the internet does not work, so how will XP recognize SP2 needs to be downloaded?

Find and remove INFCACHE.1

1. Click Start, click Run, type %systemroot%\inf, and then press Enter.
2. Find the INFCACHE.1 file that is located in Windows\Inf folder.
3. Right-click the Ie.inf file, and then click delete.

Install XP SP2 - Use the Network Installation

1. Go to
2. Download it to your desktop.
3. Run that when in safe mode

Thanks - stuck no more. GTD

Thanks !

thanks,,, it works :)

F---ing A... Worked like a charm... THANKS ALL! NYC...

I just wanted to say...OUTSTANDING!!!!!!! I have been working on the laptop for 2 days trying to get SP2 in. Did what you said and Whalaa! it worked. Thanks to the guy that posted and also to the guy that found it.

Thank you so much this is a miracle solution. It went through no problem... I did not finish the installation yet, but seams to work good...

excellent post well done! worked like a charm!

Absolutly brilliant, I fought for 2 days to get sp2 installed. This helped. Thnx

The INF Directory is in the windows folder, to get to this to C Drive, The folder is hidden though

INFCACHE.1 stay in Windows/inf the same directory of oem*.inf files.

Thank you sooooooooooo much. This trick really works . Saved me lots of time..

thank you !!

thanks a lot. You've provided a great service to humanity...well maybe just computer users. thanks a lot!!!!

You are the men. worked like a clock Commnent I didn't need to delete the cach however it still worked. Or

worked fine on packard bell easynote after two days of trying other solutions - many thanks

it works! thanks! also, it looks like it removed the product activation... (i say the "keys" icon in the taskbar again...) but no big deal. it saved me a bunch of work.