No-execute and execute protection are all names for DEP. This process feature increases security, but may cause problems with certain programs.
Several OSs have no-execute or execute protection. Microsoft has added this as well in SP2 with data execution prevention (DEP). This precents code execution in memory regions already marked as storage. This is a powerful tool against buffer overrun exploits.
If a program is failing and you want to disable DEP to see if that is the cause. Here are the steps. (Just disable DEP for the program in question... don't disable it for your whole system.)
1. Click Start
2. Select Control Panel
3. Select System
4. Click the Advanced tab
5. In the Performance region select Settings
6. Click the Data Execute tab in the dialog box that opens
7. Select Turn on DEP for all programs and services except for those I select
8. Click Add.
9. The open dialog box will open. Browse and select your application.
10. Click Open
11. Click Apply
12. Click Ok
Also, check your boot.ini file (open with wordpad or notepad)...it should look similar to this:
multi(0)disk(0)rdisk(1)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /NoExecute=OptIn
multi(0)disk(0)rdisk(1)partition(2)\WINDOWS="Microsoft Windows XP Professional x86_64" /fastdetect
Excuse my ignorance, but even though SP2 might have buffer overflow prevention, I thought you would need to take full advantage of the x86-64's architecture to run this feature, thus needing a 64 bit OS and getting that LMA mode running. But if it works with SP2 what does this mean?