Lost access to C:\ Drive. "Can't open access control editor. Access is denied" error is displayed

I recently bought a new Dell Studio XPS 435T (last Wednesday)

Last night I tried to change a property on an Excel File I created years ago, and the machine told me 'Access denied' and the Security pop-up was displayed.

After cancelling out of the pop-up, I was asked to restart the PC

After the PC rebooted, my C:\ drive displays 'Access Denied (C:)'

When clicking on C:\, the following message appears

"Location is not available

C:\ is not accessible

Access is denied"

When following Microsft Help's instruction to 'Take Ownership' of the file/folder. I receive

'Can't open access control editor.  Access is denied'

Is there a way to regain access to the drive WITHOUT losing my old data that was transferred (the PC it came from has since been re-imaged and sold)

I thought I had purchased software support from Dell, but apparently it was only Hardware support.

Also, as I am still in the process of setting it up - I have not created a restore point yet.

So................I would like to regain control of my PC
 - without a known System Restore Point
 - without losing any of my personal data that I transferred to the C drive

Question Info

Last updated February 25, 2020 Views 97,978 Applies to:
Hi Cyrenaica1967,
Welcome back to Microsoft Answers Forum!

1. Login in to “Safe mode with Command Prompt”.

Follow the steps below in order to get into “Safe mode with Command Prompt”:


1. Restart the Computer and start tapping the function key - F8 on the keyboard to access the advanced boot options.


2. Using the arrow keys on the keyboard, select "Safe mode with Command Prompt” option and hit Enter.

3. Log on to your computer with a user account that has administrator rights.

You can also refer the links below for further reference:




2. At the command prompt, type - NET USER Administrator /active:yes

The key is to be able to login as administrator.

Don’t worry if you get an error message, you might have to do some of the following steps.

3. Try NET STOP ProfSvc

This should stop the User profile service and bring you back to the login page - and if you are lucky you will have an Administrator login there.

It might not have a password if you did not set up a password when you configured the system.

3. Control Alt Delete, start task manager, Applications, New Task, explorer - this should bring up the start menu etc

4. Disable UAC [User Account Control] which might give access to your C: Drive.
Follow the steps below in order to disable UAC.

A. Open Control Panel.

B.Under User Account and Family settings click on the "Add or remove user account".

Click on one of the user accounts, for example you can use the Guest account.

D.Under the user account click on the "Go to the main User Account page" link.

E. Under “Make changes to your user account" click on the "Change security settings" link.

F. In the "Turn on User Account Control (UAC) to make your computer more secure” click to unselect the "Use User Account Control (UAC) to help protect your computer".

G. Click on the Ok button.

You can also refer the link below for further information on User Account Control:


. Once UAC is disabled - Right click on C:Drive> click Properties > Security >Advance > Effective Permission > Select > enter ( your name )\administrators > click OK.

You should now regain full control of your computer.

Please inform if it is successful or not. Good luck.


Manasa P-Microsoft Support

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