XFOR: Error Message: Extension MS Could Not Be Loaded

When you use the Microsoft Exchange Server Administrator program to view the properties of the Microsoft Mail Connector object in the Connections container, the following error message may be displayed:

This issue can occur if any one of the three following conditions exists:

• The Add-Ins folder on the Exchange Server computer is not shared.
• Either the dynamic-link library (DLL) for the extension that is being loaded, Conadmin.dll, is the incorrect version or the Exchange Server directory version of the Conadmin.dll does not match the actual DLL file version.
• When you gain access to shares on a computer that is running Microsoft Windows NT Server from a Windows NT client and the IRPstackSize parameter is set too low on the server, you may receive the following error message:
  Not enough server storage is available to process this command

The Add-Ins Folder on the Exchange Server Computer Is Not Shared

To resolve this issue if the cause is the first condition in the "Cause" section of this article, set the following correct shares and permissions for the Add-ins subfolder: If the Add-ins share is not set correctly, you should also check the other default shares and permissions. For additional information, click the article number below to view the article in the Microsoft Knowledge Base:

Incorrect Version DLL for Conadmin.dll or Mismatch with Exchange Server Directory Version of Conadmin.dll and DLL File Version

To resolve this issue if the cause is the second condition in the "Cause" section of this article:

1. Verify the build version that you are using. You can do this by checking the properties in the following location:
   Organization\Site\Configuration\Server\server_name
2. Check the actual file version of the file on the hard disk drive in the following location:
   Exchsrvr\Connect\Msmcon\Bin\Conadmin.dll
3. If the versions do not match, replace the file manually from the Exchange Server computer or Exchange Server service pack CD-ROM.
4. Verify the file version for the extension DLL. This can be done by checking the properties of:
   Organization\Site\Configuration\Add-Ins\Extension for MS Mail Connector for i386
5. If the file versions do not match, change the version in the directory by using the Exchange Server Administrator program in raw mode. For additional information about how to change the value by using the Administrator program in raw mode, click the following article number to view the article in the Microsoft Knowledge Base:
   196924� You receive an "Extension 'SMTP' could not be loaded" error message in Exchange Server 5.0 and in Exchange Server 5.5

Shares on Computer Running Microsoft Windows NT Server with IRPstackSize Parameter Set Too Low Accessed from a Windows NT Client

To resolve this issue if the cause is the third condition in the "Cause" section of this article, either correct the IRPstackSize parameter or apply the fix that corrects this problem. For additional information about how to correct the IRPstackSize parameter and a fix that corrects this problem, click the article number below to view the article in the Microsoft Knowledge Base: