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In my user folder (C:/Users/myAccount/) theres a set of interesting hidden files that I've never seen before (right now it's a fresh install of Windows 7 Ultimate).

These are: NTUSER.DAT, ntuser.dat.LOG1, ntuser.dat.LOG2, and NTUSER.DAT(whole chain of numbers and letters).TM.bif, NTUSER.DAT(whole chain of numbers and letters).TMContaineretcetc.regtrans-ms, and another similar one.

When I try to delete them, it says the system is using them.

I've never seen these files before. Are they ok to delete? Or should I leave them in my home folder? I always keep "Show hidden files" as well as "Show System files" checked, since I prefer being able to see all the files on my computer.

If I shouldn't delete them, is there at least a way to tidy them up a bit?


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up vote 9 down vote accepted

NTUSER.DAT is the user's registry hive and should not be touched. The others sound like transaction logs and backups. You might be able to remove them after a reboot. If not then leave them alone.

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+1 beat me to it. – Sathya Apr 9 '10 at 22:54
Also, why would they appear now and not in my previous installations of Windows 7 Ultimate? – Vervious Apr 9 '10 at 22:56
They've been there since Windows NT. You may have "show hidden files and folders" checked. – DrFloyd5 Apr 10 '10 at 13:40
Yea I do. I'll probably just uncheck "Show System Files", since now that I think about it there's no real benefit for me to be able to see the occasional important system file. – Vervious Apr 11 '10 at 1:02
@Nano8Blazex: Precisely. There is a reason these files are hidden by default... – sleske Sep 22 '11 at 8:04

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