Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17


Bunch of problems with Win XP Pro: error 800b0100, cannot boot up Windows after trying to repair it. It's a mess.

Posted on 2008-10-18
Medium Priority
Last Modified: 2012-05-05
Hi everyone,

A few days ago my laptop started behaving odd after I logged in. I scanned it for viruses but the problem was still there. So this is what I did:
I booted up my laptop from the Dell Windows XP OS CD that came with it.
I see the blue screen that says "Windows Setup" at the top with the gray bar at the bottom that says "Setup is loading files... "
Of the three options I get, I choose the option "To setup Windows now, press Enter", then I accept the end-user agreement.

The first time I did this, it copied the files it usually copies, and then asks me what I want to do. I tell it to repair the already-existing WIndows installation. It does all it has to do an then I see the more user-friendly WIndows installation screen that tells me how long it will take to install.

It tells me it will take 39 minutes to install and almost immediately I get a messagebox with message "Fatal error: Setup failed to install the product catalogs. I click OK and I then get error "The signature for Windows XP Professional Updgrade is invalid. The error code is 800b0100".

So after I try this, Windows doesn't let me log on normally of in safe mode. Everytime I turn it off and back on I automatically get the "Setup is being restarted..."

I tried renaming directory catroot2 to catold (;EN-US;q307153) but that doesn't work.

What else can I do? I cannot go into safe mode and I cannot start up WIndows normally. I wanted to back up some stuff, but I don't want to do it via the command prompt.

I have WIndows XP Pro SP2 (not an upgrade) and it's the same exact copy that came with the laptop when I bought it. I haven't installed any new software. This is the first real problem I've had in a long time.

Any help is appreciated.
Question by:MyersA
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions

Accepted Solution

jbuzzard earned 272 total points
ID: 22751257
Firstly, I would suggest backing up your stuff. This is easiest to complete by removing the hard drive, mounting it in an external hard drive case, and plugging it into another computer (friend, parents, etc). You can then copy various things off it.
  A better way is to make an image of the hard drive, using something like Acronis True Image Home. This will be able to copy system files, hidden files etc. Basically, you can either boot from the Acronis CD (which can then copy stuff to an external drive), or you can use an installed version on a different computer.

I would then suggest you check the components of the computer using a CD bootable option. I tend to use the included tools of the Ultimate Boot CD (Free) to stress all the components and test whether they are the cause of my problem.
Make sure to test the Memory, CPU and Hard drive. Mainboard tests are difficult, and usually don't result in anything substantial.

If everything turns out normal, you can either try reinstalling windows (better option) or repairing your previous install. If you are going to try the latter, then you need to use the actual Windows XP Pro SP2 disc that you have (as long as the windows you have installed is also the Pro SP2 disc). Be aware, if you are using an OEM disc to repair a retail install, it won't like you very much and can throw errors. Try to use the same disc that you used to install in the first place.

The repair installation option is alright, but I think a reinstall would provide you with a better start point for future work.

I tend to find the need to reinstall windows every 6 months so I can clean out all the gunk that accumulates in the registry in that time.

Hope this helps.
LVL 88

Assisted Solution

rindi earned 264 total points
ID: 22751602
Test your RAM using memtest86+ and also test the HD using the disk manufacturer's diagnostic tool. You'll find both on the UBCD.
LVL 93

Expert Comment

ID: 22751606
to get you started, try this :,289483,sid68_gci1167895,00.html   

then you can do what you want...

Author Comment

ID: 22796728
Thanks for the posts. I downloaded Ultimate Boot CD.

I tested my RAM and I got a bunch of error messages with one of the modules. Would it be possible that I get errors because there's a problem with the RAM slot?

The reason I asked is because I inserted the faulty module in one of the slots and I got a bunch of errors. Then I put it in the other slot and the test passed. On the other hand, once I rebooted the laptop I got an error memory. So I'm almost certain that it's the memory module.

Can the memory slots be tested with the UBCD?

Out of curiosity, do you guys know how I can replace a GigaRam memory module that is supposedly under warranty? I only have the module (no receipt, box, etc...)

LVL 93

Assisted Solution

nobus earned 264 total points
ID: 22797015
>>  I tested my RAM and I got a bunch of error messages with one of the modules. Would it be possible that I get errors because there's a problem with the RAM slot?    <<   thet is possible, yes

you test ram, not slots - but the signals pass thru the slots, so...yes they are tested too - clean the slot thoroughly

>>  how I can replace a GigaRam memory module that is supposedly under warranty?   <<  bring it back to the supplyer

Featured Post

Simplifying Server Workload Migrations

This use case outlines the migration challenges that organizations face and how the Acronis AnyData Engine supports physical-to-physical (P2P), physical-to-virtual (P2V), virtual to physical (V2P), and cross-virtual (V2V) migration scenarios to address these challenges.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Issue: Unstable cursor in Windows XP and Windows runs extremely slow in that any click will bring up the Hour glass (sometimes for several seconds before giving you what you want) . Troubleshooting Process and the FINAL FIX: This issue see…
When you start your Windows 10 PC and got an "Operating system not found" error or just saw  "Auto repair for startup" or a blinking cursor with black screen. A loop for Auto repair will start but fix nothing.  You will be panic as there are no back…
Video by: ITPro.TV
In this episode Don builds upon the troubleshooting techniques by demonstrating how to properly monitor a vSphere deployment to detect problems before they occur. He begins the show using tools found within the vSphere suite as ends the show demonst…
Two types of users will appreciate AOMEI Backupper Pro: 1 - Those with PCIe drives (and haven't found cloning software that works on them). 2 - Those who want a fast clone of their boot drive (no re-boots needed) and it can clone your drive wh…

688 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question