Autocad 2010: AcPEXCtl.arx file causes product to not startup on Windows 7

You are trying to start Autocad Architecture 2010 and there is an error with the following file:

    AcPEXCtl.arx

If you remove the file, Autocad Architechture 2010 will start but the properties dialog box/pallet will not populate.
Solution

You will need to set the compatiblity mode for ACA to Windows XP as a local administrator account (not the domain administrator).

When you run it as a domain user, Autocad will automatically attempt to set its own compatibility mode, however, in Windows 7, the security will prevent the domain user from doing this. If you login as the local administrator on the computer and then load the software, it will have permission to make the first run permissions and security changes required for normal operation.

Once you have run it once as local adminstrator, just log out and log back in using your normal user account.

Typically, if you have setup a single user on Windows 7, ACA will start for the first time, crash and it will setup the proper compatiblity mode when you run it the second time.
Solution for Domain Users

For sites that have a large number of Autocad Architecture licenses:

1. Login to a client machine with a standard user account.

2. Create a text file, paste the following text, and then save.

Windows Registry Editor Version 5.00
[HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layers]
"C:\\Program Files\\AutoCAD Architecture 2010\\acad.exe"="DISABLEUSERCALLBACKEXCEPTION"

Note:   If AutoCAD Architecture is not installed to the default location (C:\Program Files\AutoCAD Architecture 2010), please change the path accordingly.

3. Change the file's extension from .txt to .reg.

4. Double click the file and then choose Yes so that the setting could be imported to registry.

5. Run AutoCAD Architecture  with the same user account.