Unable to Log In to Windows 2000 After Changing Drive Letters

Date Initially Written: 11 June 2003.

Problem: After my drive letters changed in Windows 2000 I was unable to log in.

Operating System: Windows 2000 Professional with service pack 3.

Background: I used Norton Ghost to backup my main hard disk to a removable hard disk. My main HDD has two partitions; a primary partition that I use for programs and a logical partition that is used for data files. My backup HDD is a mirror copy of my main HDD, so it has the same partitioning. To make a backup I inserted the backup HDD and boot up with the Norton Ghost boot floppy disk. This operation boots up DOS and runs Ghost. After the backup has completed I power down and remove the backup HDD.

One day I booted up Windows 2000 with both drives connected and logged in. My drive letters were rearranged because Windows puts primary partitions before logical partitions, resulting in the following drive letter arrangement:

C: Primary on HD1
D: Primary on HD2
E: Logical on HD1
F: Logical on HD2

After removing the backup HDD I rebooted and tried to log in. I was presented with a message saying:

Limited Virtual Memory
Your system has no paging file, or the paging file is too small.
Please use the virtual memory option of the System applet in the Control Panel to create a paging file or to increase the initial size of your paging file.

Unfortunately I was then immediately taken back to the login prompt and there was no way I could log in. Even starting up in Safe Mode wouldn't allow me to log in. Using my Emergency Repair Disk didn't help either.

Resolution Steps: After some research I found that Windows 2000 maintains a record of drive letters in the registry and re-assigns drive letters based on Globally Unique Identifiers (GUIDs) which are recorded for each volume. If the volume's GUID is modified or duplicated (i.e. by hard drive cloning software (i.e. Norton Ghost)), then the original drive letter may not be re-assigned to the boot volume.

So how to fix this problem? There are several possible ways to fix this but the easiest way that worked for me was to boot up with a Windows 95 boot disk (probably just about any old boot disk will work, if you don't have one then you can download one). Make sure that the FDISK program is on the diskette. Run the following command: FDISK /MBR

This re-writes the Master Boot Record which removes the disk signature associated with the volume's GUID. Windows 2000 then re-assigns the drive letters and allows you to log on.

Phew! I thought I had locked myself out of my computer! This trick works for both FAT and NTFS partitions.

Update (9 September 2005): It has been reported to me that the FDISK /MBR fix mentioned above may not work on SCSI drives. A fix that worked on SCSI drives was to boot from your Windows CD-ROM, select "Recovery Console" and then "FIXMBR".

Update (13 October 2005): It has been reported to me that the FIXMBR fix mentioned above may not work on SCSI drives. If FIXMBR doesn't work for your SCSI drive then I don't have a solution other than a re-format and re-install (something I hate to recommend because I often see this "solution" offered as a way to fix almost all computer problems, and I'm sure that 95% of the time it is unnecessary).

Update (20 March 2007): Simon Kwok has sent me the following useful information:

Unfortunately this method didn't work for me because my computers main drive was set up as F. I did have enough partitions on the computer to have listed up to F if i did a fix mbr but it still didnt work after a few times and also trying foward/front slash. I believe it might have been b/c it was ntfs.

In any case, i had found another solution. While the computer still has that virtual memory error message, the computer is on and on the network. I took another computer (windows xp) and logged in as a user other than the one logged into windows 2000 (dead) machine (for both of my computers i have the same login names). Then i did "net use \\computername\IPC$ /user:administrator *" and then typed in the admin password and when it says "connection successful" or something to that effect, i used regedit, then go to file, and then select connect to remote computer, typed in remote computer name, and then started fixing the registry. I then followed the steps on the microsoft about changing certain registry entries to enable the machine to login (it was under the heading of Winlogin but cant remember the exact location of the key). Also, i changed the location of the pagefile thru the registry and then proceeded to change random entries.

Hope you can add this onto your page to inform others about this solution. This solution is posed on random sites but the info was spotty at best. You might also want to collect some data on the function net use in case it doesnt work for others. I didnt work for me at first until i logged into my xp machine with another user then dialed into my win2k machine.

Recommended Reading For Solving Windows XP Problems: Microsoft Windows XP Inside Out, Second Edition

Comments From People Who Had This Problem:

Name: James Lauritzen
Comment: Murray, you are a god that walks the earth. I also had the 'page file' problem and 'Googled' my way to your site. The 'fdisk /mbr fix' fixed my issue as well and I will be forever grateful.

Name: Mario
Comment: I can't stop from praising you. You saved me from an all nighter on Sunday 11/02/03. My credit card processing machine's hard drive went out on me yesterday. No big deal I thought. Well guess what? I had used Norton Ghost to make a copy of the hardrive and I got the dreaded "Page File not big enough" and not able to log in. Your piece described exactly my scenario, and your fix worked like a charm. You saved me from having to rebuild a Windows 2000 machine from scratch plus configure all the bank codes for it to be able to start processing payments again. Keep up the good work.

Name: Brian S.
Comment: I spent 3 hours on the junk site of microsoft and found nothing that would help! I found your site and this simple fix "fdisk /mbr" fixed the pagefile error I was having. Nice Job Sir!

Name: Keith Hillis
Comment: Murray - saved my @#! tonight. Friday night stuck at work late but leaving now because Master Murray comes through in the clutch.
(bows to the master)
I am not worthy!!!
Thanks bud,
~Keith

Name: Joe
Comment: You are a definite genius - wasted 2 hours on a new win2k system with no paging file on a ntfs disk - ran win98se boot disk and even though it could not see c drive I was desperate and ran fdisk/mbr - EUREKA!

Name: Roger
Comment: Murray, god bless you!!!!!!!!
I too had the famous locked out of my drive via the you dont have a page file and returned to the logon screen deal. ARGHGH I have 2 drives in my system and 2 drives from another system I wanted to add just to pull off the files. The first drive was no prob. So I shut down and connect the second drive after removing the first and boot up to find no page files bla bla bla. I removed the drive still nothing... tried last known good config and nothing. Finally I went to my other computer and scaned the net feeling pretty alone in that I'm sure I was the only one ever to have this prob and theres no fix :) Anyways I came to your page and you took the words right out of my mouth, it was like you were right here going through this with me. Thanks again for that simple solution fdisk /mbr. I was familiar with it but didn't think it would apply to this. Boy was I wrong! Thanks again my friend you saved me a couple of hours reinstalling.

Name: Matt
Comment: Thank you so much Murray! I had the same exact problem you did, when you described the issue using Norton Ghost and a 2nd harddrive. When I rebooted, I was locked out of my system by the devious "page file not found" error. I found your site, used the FDISK /MBR quick fix and VOILA! My machine booted right up. Thanks to you (and not the hour I spent on the MS site looking for an answer) for helping this junior administrator out! Thanks!

Name: Ray Firth
Comment: Murray, you are a bloody genius! Just when I thought I had wrecked a client's machine by cloning the HDD with Ghost and the getting the Limited Virtual Memory error. Your advice was right on the mark. May the gods shower you with many many riches :)

Name: tom p.
Comment: Murray, you are the man! the fdisk /mbr fix is pure genius. I promise to frequent your site and will reciprocate, if ever possible. Cannot tell you how very impressed I am with you and your level of expertise. More power to you!

Name: Bob Westlake
Comment: Murray, you are a god that walks the earth. I also had the 'page file' problem and 'Googled' my way to your site. The 'fdisk /mbr fix' fixed my issue as well and I will be forever grateful. Murray, I had the 'page file' problem and 'Googled' my way to your site. The 'fdisk /mbr fix' worked like a magic bullet and I am now deeply in your debt. There should be more like you on the Net. Your nine characters were far more effective than several pages of incomprehensible Microsoftese, and you are now on my 'Favorites" list, along with Nick Bolton at Firetrust. New Zealand must be a nice place to live - it's full of nice people!

Name: Gary Armstrong
Comment: The FDISK /MBR fix after copying a drive with Norton Ghost is brilliant. To fellow readers, I point out that FIXMBR in the W2K recovery environment did not work for me. But booting W98 and running FDISK /MBR worked perfectly. Thanks, Murray!!!!!

Name: Jon Stagy
Comment: I Echo Gary Armstrong's experience. I had a problem adding a second disk with an OS on it already and my jumpers must have been wrong. Came across Murray's site, my hopes were instantly raised, tried the recovery console method to no avail just because it was easier but a WIN 98 boot disk did the trick. Your the best!
The FDISK /MBR fix after copying a drive with Norton Ghost is brilliant. To fellow readers, I point out that FIXMBR in the W2K recovery environment did not work for me. But booting W98 and running FDISK /MBR worked perfectly. Thanks, Murray!!!!!

Name: The New Pope in Rome
Comment: You've really saved our holy axx over here at the Vatican. We knew that Satan had sway over the lads of Redmond, but we really had a big problem when it came to increasing our partitions and suddenly being locked out and then having no access to our Win2000 computers at all, with all of our files of blessings, good deeds, and real estate transactions.
The Council of Rome met and have decided to elect you to SAINTHOOD. Yes, Saint Murray, the Patron Saint of screwed-up paging files. We voted and don't even care if you are gay. I've now proclaimed that Dec 20, the day that the Vatican's Win2K computers were saved as "FDISK /mbr DAY".
As we say over here in Rome, 'ecce homo', or translated, "YOU DA MAN!". Peace and blessings.
The Pope