Come Join Us!

Are you a
Computer / IT professional?
Join Tek-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Tek-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.


Jobs from Indeed

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

how to reset permissions on c: drive?

how to reset permissions on c: drive?

Help!  I accidentally changed the permissions on my WinXP C: drive to exclude anybody but my log-on name.  I deleted the "Everyone" permissions and all that was left was my log-on name with permission.

I cannot boot now.  I get a "Fatal System Error" (STOP: c000021a) ...  presumably because even the system cannot access the partition?

How can I boot from a CD or somehow change the permissions to let the system access the drive?  I don't have a Windows XP CD, just a System Restore disk from the manufacturer.  I'd like to just reset the permissions rather than reinstall from scratch, if possible.

RE: how to reset permissions on c: drive?

I think your best bet would be a BARTPE Cd, these can come in many flavours - my personal fave can be found here

This will give you access to the drive and allow you to set the permissions again.

Greg Palmer
Freeware Utilities for Windows Administrators.

RE: how to reset permissions on c: drive?

Thanks, Greg.  On a Google search I found BartPE, and downloaded/burnt the ISO image, but don't know how to set the permissions using any of the utilities.  Can you please hold my hand a little bit further?  Which utility can set the partition's permissions for my C:?

RE: how to reset permissions on c: drive?

Greg:  Is there a way that I can use without being booted into Windows?

I tried using secedit in BartPE, but it's not included.

What I need is a way to reset the permissions from outside of my WinXP installation.

Using BartPE's "A43 File Management Utility" (equivalent to Explorer), when I right-click on C: Local Disk, it shows "File system: RAW" with capacity, used space and free space as 0 bytes.  I need some way to be able to turn the permissions back on.

RE: how to reset permissions on c: drive?

Can you boot to safe mode/command prompt only?

You could run cacls from there, perhaps....

Just my 2¢
-There once was a man from Peru
 Who wanted to write a Haiku


RE: how to reset permissions on c: drive?

No, I cannot boot into any form of Windows.  I get a "Fatal System Error" (STOP: c000021a) BSOD.

I had hoped cacls would be included in BartPE, but sadly it isn't.  <sigh...>

BTW, this is a notebook computer with no floppy drive.  I tried using an old PCMCIA floppy drive, but it is not recognized by the BIOS to boot from, nor by BartPE or any form of DOS ISO's that I burnt to CD and booted from.

One tactic I was considering was somehow to get Partition Magic for DOS up and running, and then convert the partition from NTFS to FAT32 and see if that would work, thinking it would strip permissions off when it converted to FAT32.  (Is there any freeware to convert a bootable floppy with Partition Magic on it to a bootable CD?)  I tried Bart's boot-to-DOS CD, but it puts any user-added files on the root level of the CD, but my CD is external (via FireWire), and DOS can't access the user-added files, such as the PM files.

How risky would that be to data on the drive?

Thanks for the brainstorming with me!

RE: how to reset permissions on c: drive?

I had another bright idea:  There is a 7GB partition available on the notebook and a friend lent me a bootleg Windows XP disk and thought I would install a second instance of XP and from within that, change the permissions on my C: drive to "everyone".

The installation stuck on "cannot copy ntldr".  Apparently even the WinXP installation program cannot write to the C: drive where ntldr  must reside.  <sigh....>

Isn't there a way to run a "repair" installation of WinXP from the CD?  (I don't have an ASR floppy, unfortunately, so cannot run ASR.)  Maybe it's because it's a bootleg WinXP disk that's been modified, but I can't seem to find a way to "repair" from the CD...

RE: how to reset permissions on c: drive?

HALLELUJAH!  I finally got it back up and running.

Since I had a 2.5" hard drive enclosure, I decided to dismantle the notebook and remove the hard drive.  Turns out I didn't have to dismantle the notebook, since it's a nice modular design and with removal of two screws I could have slid out the drive WITHOUT removing those other 20 screws.  But, it was more fun trying to re-attach the keyboard ribbon cable that I dislodged...

Anyway, after I found that my hard drive was SATA and my hard drive enclosure was PATA, I went out and bought a cheap SATA hard drive enclosure, USB'd it to my desktop computer where I was able to convert the C: on the 2.5" drive from NTFS to FAT32 using Partition Magic.  

When I re-inserted the hard drive into the notebook and booted up, it said ntldr was missing, so I booted from the bootleg WinXP CD to start an installation in an empty partition, knowing it would place a copy of ntldr in the root directory of C:.  At the first re-boot in the install process, I quickly used to arrow keys to change the boot menu to my previous WinXP installation, and voila! it booted as if nothing had happened.  I modified boot.ini so that the timeout=0 (no waiting for boot menu), re-converted the C: partition to NTFS, and I'm back where I started.

What a relief!

To the two Gregs who replied:  Thanks again for your time and assistance.

To the rest of the readers: I hope you enjoyed the ride with me, and hope that maybe someone else learned something from my adventure.

RE: how to reset permissions on c: drive?


Isn't there a way to run a "repair" installation of WinXP from the CD?


Boot from the CD, don't take the first "R" (recovery console)...when the CD looks for a previous installation of WinXP, it will ask you if you want to repair it.  Take THAT "R" choice.

But I'm glad you got it fixed.

Just my 2¢
-There once was a man from Peru
 Who wanted to write a Haiku


RE: how to reset permissions on c: drive?



Boot from the CD, don't take the first "R" (recovery console)...when the CD looks for a previous installation of WinXP, it will ask you if you want to repair it.  Take THAT "R" choice.
That's what I thought I remembered, but the bootleg CD I was using must have been altered in a way that rendered that option unavailable.  When starting the installation process and selecting the partition I expected such a prompt, but never got one.  Even when I selected the C: partition, it was simply going to format it and install there.

BTW, I live in Thailand, and the bootleg/counterfeit software industry is a sizeable one.  The counterfeit WinXP CD allows installation with no activation ever required.  There are hacks to disable even the latest versions of Genuine Advantage.  I don't condone using counterfeit software, but in this case was simply desperate to re-enable a valid WinXP installation.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Tek-Tips Forums free from inappropriate posts.
The Tek-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Tek-Tips forums is a member-only feature.

Click Here to join Tek-Tips and talk with other members!


Close Box

Join Tek-Tips® Today!

Join your peers on the Internet's largest technical computer professional community.
It's easy to join and it's free.

Here's Why Members Love Tek-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close