Delete Windows XP NTUSER.DAT File Free Up Disk Space
Windows XP system automatically pops up a window which informs the user that the disk space is running low. Low disk space left is a probable cause of computer slowing down. The reason could be that the system is creating some temporary files on the hard disk and there’s no more space available.
I have observed that when the disk space runs low the computer is prone to hung ups and is very slow in responding to any request. Opening multiple software application window would take nearly a minute and worst it would sometime not respond. An error not responding is thrown. Having ample disk space to accommodate temporary files created by the system while running Windows XP would be necessary for better computer performance.
The computer files that would impact in freeing up disk space are those that have more than 100Mb in size. Thus, I search for them in the computer for possible deletion whenever necessary. I have found many files with File Extension DAT could at times eat up 1 GB of disk space. By deleting these large files I would immediately get the needed space for running smoothly my computer.
There are many large size files that lurks in the computer which takes a lot of disk space. Some computer program files have data files with File Extension DAT which is needed at run time or during installation. I have noted that files with DAT extension takes up space. Some of them contains temporary data which don’t have any impact even if deleted. There are some also that have very significant importance that when corrupted would cause the computer hang up.
An example of a DAT file is Ntuser.dat which is created by Windows XP system during user profile creation. The file size of ntuser.dat on a fresh installation of Windows XP is only about 256 Kb, but as time goes on the file grows in size up to even 9 GB or more. Thus, ntuser.dat file is a very good file candidate with File Extension DAT for deletion to free up system disk space. I tried deleting ntuser.dat and it seems there’s no adverse effect. A notable effect is Windows XP theme was reset to use the non-Windows XP default ordinary theme.
A special thing about ntuser.dat file is whenever it’s deleted there’s no need to worry as it is created back whenever the user logs into the system. A friendly note, if you’re thinking about deleting NTUSER.DAT.
DO NOT DELETE NTUSER.DAT as you’ll LOOSE your PROFILE SETTINGS
Remember NTUSER.DAT is a required system file and may cause your system to crash. It’s possible though to delete it, but DON’T BLAME me for anything. If you do not know what you’re doing then – DO NOT DELETE NTUSER.DAT.
If you want to test the effect then it’s important to backup NTUSER.DAT before doing anything on it or deleting it for disk space saving. There might be particular settings on your Windows XP which you might want back later. It’s better to be safe than to be sorry for lost data.

Posted on
Sunday, March 29th, 2009 at 10:53 pm under 
What the hell?! ntuser.dat is a REQUIRED system file! That file stores all the specific information for the given profile. Specifically, it is everything in HKEY_CURRENT_USER in the registry.
Do NOT delete that file as it could severely screw up your installed programs as well as windows itself!
April 9th, 2009 at 7:03 amI really hope this was your idea (in poor taste, nonetheless) of an April Fool’s joke. Delete the NTUSER.dat file? Seriously? While you are at it you should go ahead and revoke your logon credentials…OH wait.. You meant to hose your system anyway, so why bother. This is a very poor idea, even in theory. Please, don’t suggest this file for deletion, as it is a REQUIRED system file.Yes, it will get rebuilt, as you are going to have to REBUILD ALL OF YOUR PROFILE SETTINGS, since this will remove all of them..Man oh man , I could go on for days as to how ridiculous this ‘tip’ is.
April 24th, 2009 at 4:21 amThanks for reminding about taking precaution in deleting NTUSER.DAT.
May 8th, 2009 at 2:02 pmI would not delete the ntuser.dat.
did it once and could not boot. Had to fresh install.
This article is in rather bad taste.
May 20th, 2009 at 2:01 pmDo NOT do what this writer suggests. If you do do this then you DO NOT KNOW WHAT YOU ARE DOING … and so, as the author suggests, you should not do it. Seriously. Don’t do it.
September 11th, 2009 at 5:21 amUnder no circumstances should you delete Ntuser.dat. The stores your entire personal Registry hive. And if deleted you will have to reinstall the OS 9/10 times. The one time in a long shot it doesn’t require and install be ready for every error you have seen in your life as your entire registry will be incorrect. This is not an option if you are running out of disk space. for all you downloader. make mp3 discs of music and run your music from cd drive. get ATF cleaner and run it. OR get a new hard drive. IT’s better than loosing everything from doing an OS reinstall.
November 12th, 2009 at 6:31 amDeleting ntuser.dat isn’t dangerous at all- but of course MOVING the file instead of deleting it is always the better idea, in case something goes wrong. In that case, you can always login as another (admin) user and restore the file.
November 17th, 2009 at 1:28 pmOf course doing so requires no autologin, and some other user acccount being present.
Sure enough, dumb users shouldn’t delete that file, but I’m pretty sure thay can find other, easier ways to irreperably screw their system.
i had 3 unused profile& i could delete 1 profiles ntuser.dat file , but why not others? i dont know.May be it is required file
April 8th, 2010 at 2:51 pmIf you are in a domain setting then deleting ntuser.dat files on unused profiles (IE the entire profile folder) IS ok to do, assuming the profile in question is not the Administrator account.
June 25th, 2010 at 1:47 am