If you launch Pro Tools 10 with DEP disabled, the symptom occurs.

Please enable DEP.

Enable DEP
This troubleshoot can sometimes help resolve issues with installing and launching Pro Tools software. If you have disabled this for any reason, it is often recommended to re-enable it.

1.Open the Start menu and type “cmd” (without the quotations). The Result you get should be “cmd.exe”.

2.Right-click on “cmd.exe” and choose “Run as administrator”.

3.Click the Allow button if it asks you for permission.

4.Type or copy & paste this into the command prompt window:
bcdedit.exe /set {current} nx OptIn

5.Hit enter and you should see the confirmation: Operation Completed Successfully.

6.Restart the computer and DEP should be on for the entire system.

If the symptom still occurs, please clean uninstall and reinstall Pro Tools 10.