Active Directory Users and Computers Error: “the application has requested the runtime to terminate it in an unusual way”

UPDATE [6/19/2009]:  Below is my original fix for this problem however in the comments section frymaster provided an alternative.  I am no longer running Vista 64 so haven’t tested it but another user has confirmed it worked for him.

Try deleting this file:

%userprofile%\appdata\Roaming\Microsoft\MMC\dsa

It will be recreated after you shut down your MMC console.

Thanks to frymaster for the update!

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[Original Post]

I installed the newest version of RSAT for Vista Service Pack 1.  I am running the 64-bit Version of Vista.

After installing this newest version I got this error when trying to start Active Directory Users and Computers:

Microsoft Visual C++ Runtime Library
“the application has requested the runtime to terminate it in an unusual way”

I could not find an answer anywhere, I was able to open up the Management Console (mmc.exe) and browse to the .msc file (dsa.msc) manually and it would open just fine.

I went looking for command line parameters for mmc.exe and here is what I found:

MMC command-line options

Using MMC command-line options, you can open a specific MMC console, open MMC in author mode, or specify that the 32-bit or 64-bit version of MMC is opened.

Syntax

mmcpath\filename.msc[/a] [/64] [/32]

Parameters

path \ filename.msc

Starts MMC and opens a saved console. You need to specify the complete path and file name for the saved console file. If you do not specify a console file, MMC opens a new console.

/a

Opens a saved console in author mode. Used to make changes to saved consoles.

/64

Opens the 64-bit version of MMC (MMC64). Use this option only if you are running a Microsoft 64-bit operating system and want to use a 64-bit snap-in.

/32

Opens the 32-bit version of MMC (MMC32). When running a Microsoft 64-bit operating system, you can run 32-bit snap-ins by opening MMC with this command-line option when you have 32-bit only snap-ins.

• Source: http://technet.microsoft.com/en-us/library/cc757725.aspx

The short cut for Active Directory Users and Computers points to:

%SystemRoot%\system32\dsa.msc

Adding the “/64” flag to the Target of the shortcut fixed the problem

%SystemRoot%\system32\dsa.msc /64

After that, no more errors!