Helping people with computers... one answer at a time.

Folders with random and unreadable names will occasionally appear on your machine. They're typically the side effect of an update that didn't clean up.

I found these two entries while using Windows Explorer in Local Disk C:


What do they mean? Can I safely delete them or transfer them to My Documents?

What they are is easy.

Whether or not you can, or should, delete them depends on where they are.

These folders are most often created by various update utilities - most often Windows update - as temporary locations to store files before or while the update is applies to your machine. They're supposed to be deleted automatically when the update is finished. But as you've experienced, that's not always the case.

Same for me, by the way. I just found a folder "C:\66b56c24fd10a4d55d658cce1cc19e" on my machine.

If you have more than one drive, you may find them on drives other than C: as well. I've found them on my external hard drive, E:, on occasion as well.

"If you're paranoid - and it's often good to be paranoid - you can always copy the folder to some other location..."

The short answer is that if these folders exist at the root of one of your drives, you're quite safe to delete them, particularly if they've been around for a while. They're just unnecessary leftovers from a previous software update.

If you're paranoid - and it's often good to be paranoid - you can always copy the folder to some other location or burn it to a CD. That way in case we were wrong, in case something appears to start misbehaving after removing the folder, you can always restore it from the backup.

Me? I just deleted "C:\66b56c24fd10a4d55d658cce1cc19e" from my machine.

One caveat: if you find these folders anywhere underneath your Windows directory, I'd be tempted to leave them alone. I've seen comments that it's possible that they might hold the updated files for a possible uninstall, or for Windows System File Protection. As long as they're not taking up much space, then they're fairly benign anyway.

However if you can't resist and want to delete them anyway, then I definitely recommend copying them somewhere for safety first, just in case.

Article C2915 - January 30, 2007 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

January 30, 2007 4:59 PM

Is there a recognised algorithm the generate truly random number strings? Twenty years ago it seemed to be the pursuit of computer scientists. Has it been achieved yet?

January 31, 2007 9:42 AM

Anything generated by an algorithm is, by definition, not truly "random".

ezra BM
February 6, 2007 6:46 AM

Your remarks concerning odd named files- I (have) had one on my physical second Hard Drive D: - turned out to be a text files of a logging sequence.
I just deleted it, but did a Restore point beforehand- I have XP Home.
Thanks Leo, your answer helped.
I am a newcomer to your Newsletter.

May 3, 2007 5:55 PM

Hmm...well, what if those Random Folders refuse to be deleted because they claim they are being used by a program even though there are no files inside? I can successfully remove all of those random folders except for one stubborn one which will probably remain for the remainder of the life of my computer. So annoying!

May 16, 2007 2:06 AM

Everybody runs into files or folders that you can't delete because they are in use or something. The program "unlocker" which you can get here: takes care of that problem very easily. I use it regularly and recommend it.

John Booth
May 1, 2008 2:33 PM

have two folders on external drive E: Properties are:

I cannot delete these folders nor their contents, get Cannot delete (filename)ACCESS DENIED. They have been there for months. Unlocker does not work on them. Booted in safe mode, .. same problem. Have ticket open with Microsoft Support, but so far, nothing back from them. XP Home SP2.

July 28, 2008 1:58 AM

Nice and important article Leo , thanks.
John i think these files is necesary for Xp system , any way if you didn't like to be these folders visible in your drive , just make them hidden from the folders option for these folders "eb99fa32721d7821dfea81e9" "be0224887b466ec6b6ba11edbaa265"...

December 24, 2008 1:57 PM

If you get an access denied error, note the file name, and boot of your XP disc into the Recovery Console. Trust me, you can't miss it.

Then, type in

del (Drive Letter):\(Filename)

Example: C:\62sdf0ajsf2adfs

December 30, 2008 9:04 AM

Ahh.. thanks for the information.
You're awesome.

I had three oddly named folders in the root of my E:\ drive, and now those ugly folders are gone. :]

January 5, 2009 11:14 AM

If you are unable to delete the folders, you need to take ownership of the folder and sub folders and files.
First remove "use simple file sharing"
In explorer Tools-Folder Options-View then uncheck "use simple file sharing" at the bottom of the list.
This will enable the security tab when you right click on the folder and access the properties page.

Select the security tab and click advanced.

Select the owner tab then select your user account and check replace owner on subcontainer, then click apply.

You should be able to delete the folder subfolders and files.

Hope this helps

January 13, 2009 1:13 PM

If you are unable to delete the folders, you need to take ownership of the folder and sub folders and files.
First remove "use simple file sharing"...

Thanks David.

If that doesnt work for you (I did not for me) try this:

Right click on the folder>Properties>Security.
Click on your account. At the bottom check the "Allow" box for "Full Control" option.

Im using XPSP2 Pro on a corperate image...

January 16, 2009 3:12 AM

I have an external hd that I used to use on my XPSP3 machine that has 6 of these folders on it, and nothing I do (setting permissions, security etc) is working to remove these files. Formatting the drive is out of the question, as the drive hold artwork and photography projects. How can I get rid of them?

January 16, 2009 3:14 AM

Forgot to mention, using the external drive for my Vista Home Premium.

November 1, 2009 12:56 PM

I found a combo of David's steps and Jesse's suggestion to work for every set of folders I had of this type. Try both suggestions, and make sure you select 'replace permission entries on all child...'. Make sure when you switch ownership, it's to a user with Admin rights and you then give it full permissions.

Thanks guys - this was a big annoyance on all my NTFS removeable drives.

Manit Churanakoses
August 6, 2010 4:04 PM

It works for me, based on Leo's recommendations:
Properties, Security, Full Control.
I have to do one for each folder (I got 4 folders).
So I deleted them at a time...

Thank you.

Oddly I queried my question and in less than 2 minutes I got my answer.
October 19, 2011 7:41 PM

I searched Yahoo, Google, and Bing. I got the dumbest answers. I was completed disgusted. I have used the internet since its arrival. I have used computers since 1984 approx. The internet is completely corrupted of commercialism. I use less and less and am not afraid to caution many of its illicit propagation. I am thankful for those websites like yours. The gimme society of IT is repugnant.

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