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Turning Off Data Execution Prevention (DEP)

If you can find the control panel for DEP, you will find there is not an option to turn it off.  This is not a terrible thing unless you are trying to troubleshoot a problem.  Then you want to eliminate it as an issue, to confirm that the application will work in the environment as a whole.  Then you can re enable it and try to configure DEP correctly to allow your application to function:

Access to DEP configuration panel-

1.       Click Start, click Run, type sysdm.cpl, and then click OK.

2.       On the Advanced tab, under Performance, click Settings.

3.       On the Data Execution Prevention tab, use one of the following procedures:

a.       Click Turn on DEP for essential Windows programs and services only to select the OptIn policy.

b.      Click Turn on DEP for all programs and services except those I select to select the OptOut policy, and then click Add to add the programs that you do not want to use the DEP feature.

4.       Click OK two times.

There are actually 4 global configurations for DEP-




This setting is the default configuration. On systems with processors that can implement hardware-enforced DEP, DEP is enabled by default for limited system binaries and programs that "opt-in." With this option, only Windows system binaries are covered by DEP by default.


DEP is enabled by default for all processes. You can manually create a list of specific programs that do not have DEP applied by using the System dialog box in Control Panel. Information technology (IT) professionals can use the Application Compatibility Toolkit to "opt-out" one or more programs from DEP protection. System compatibility fixes, or shims, for DEP do take effect.


This setting provides full DEP coverage for the whole system. All processes always run with DEP applied. The exceptions list to exempt specific programs from DEP protection is not available. System compatibility fixes for DEP do not take effect. Programs that have been opted-out by using the Application Compatibility Toolkit run with DEP applied.


This setting does not provide any DEP coverage for any part of the system, regardless of hardware DEP support. The processor does not run in PAE mode unless the /PAE option is present in the Boot.ini file.

To turn off DEP globally, we must edit the Boot.ini file.  Here are some instructions and an example of a Boot.ini file.-

1.       Click Start, right-click My Computer, and then click Properties.

2.       Click the Advanced tab, and then click Settings under the Startup and Recovery field.

3.       In the System startup field, click Edit. The Boot.ini file opens in Notepad.

4.       In Notepad, click Find on the Edit menu.

5.       In the Find what box, type /noexecute, and then click Find Next.

6.       In the Find dialog box, click Cancel.

7.       Replace policy_level with AlwaysOff

Example of a Boot.ini file with /NoExecute set to AlwaysOff-

[boot loader]
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /NoExecute=AlwaysOff


Print | posted on Wednesday, June 3, 2009 4:29 PM |



# re: Turning Off Data Execution Prevention (DEP)

I do all the above however there is not an edit button under the Systems startup field????
11/14/2009 11:25 PM | Heather

# re: Turning Off Data Execution Prevention (DEP)

Are you an administrator on the server?

I am currently playing with Windows 7 and checked to see what has changed. DEP can no longer be disabled as described above. A quick search did bring up a method for disabling DEP in Vista and Win 7 (I skipped Vista -tried it and ditched it).

11/14/2009 11:45 PM | Geordie

# re: Turning Off Data Execution Prevention (DEP)

There's no edit button on the start-up field, is that correct?
1/9/2010 4:42 PM | Jaycie

# re: Turning Off Data Execution Prevention (DEP)

I did the dep alwaysoff then my computer restarted now all it does is take me to the black screen to select safe modes or start normaly. any one i pick it boots for a couple of seconds then goes right back to the safe mode selection
1/12/2010 9:21 PM | arthur webb

# re: Turning Off Data Execution Prevention (DEP)

Are you on a Windows XP computer?

If so and you think turning off DEP is responsible for the booting problem modifying the Boot.ini file back to its previous setting is easy if you have access to another PC running the same OS.

Remove the hard drive from the PC with the problem and connect it to the alternative PC with a hard drive dock (I use a Blacx docking station). The Boot.ini file is in the root folder of the drive the OS is installed on. Open it in notepad and reset the DEP parameter to the old value.

Reinstall the Hard drive and reboot.

1/13/2010 12:43 AM | Geordie

# re: Turning Off Data Execution Prevention (DEP)

There is no edit in "System Startup"
1/17/2010 12:54 AM | Brent

# re: Turning Off Data Execution Prevention (DEP)

Awesome trick, really its works guys thankzzzzzzzzzzzzzzzzzzzzzzzzzzz
7/19/2010 2:06 PM | Alizio

# re: Turning Off Data Execution Prevention (DEP)

This is for Win7 64 Ultimate.

For some reason, DEP has been set to 1 (always on) rather than 2, the default. Therefore the radio buttons are not activated. How do I reset to 2?

Thank you.
1/16/2011 9:40 AM | Starbuck

# re: Turning Off Data Execution Prevention (DEP)

I use a web design program to edit my websites. More specifically I use When I try to navigate around while editing it kicks out the website and tells me DEP has prevented the website from harming my computer. I know that it is not harming my computer and When I tried to use this to turn off DEP it doesn't work, it still kicks me and gives me the same DEP screen. Because of this I am having to use an unupdated version of explorer 7. But my computer will still some how find a way to update the program and I am constantly fighting this. The websites I manage are the the Leaders in their respective fields and having this problem is killing me. Any advice would be great in getting DEP off my unit.
2/23/2012 2:26 PM | Curtis Knowles

# re: Turning Off Data Execution Prevention (DEP)

Pl. Re Soluation This Problem.
5/19/2012 12:18 AM | Anirudha

# re: Turning Off Data Execution Prevention (DEP)

THANK YOU ! This worked !!!
8/29/2012 8:47 AM | Tracy

# re: Turning Off Data Execution Prevention (DEP)

It worked...thanks a lot....
3/5/2013 6:56 AM | Donnie
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