MAPI 0x80040154 error occurs when starting Exchange 5.5 Event Service

When you attempt to start the Microsoft Exchange Event Service, the service does not start, and you receive the following error message: The application event log reports the following event:

This error can occur when the following .dll files are unregistered:

• Scripto.dll
• Ss.dll
• Esconf.dll

This error can also occur when you uninstall Winsock Proxy Client from a server running Microsoft Exchange Server 5.5.

To resolve this issue, follow these steps:

1. Type the following commands, and press ENTER after each line:
   regsvr32 exchangedir\bin\scripto.dll
   regsvr32 exchangedir\bin\ss.dll
   regsvr32 exchangedir\bin\esconf.dll
   Note The exchangedir placeholder is the directory in which Exchange Server is installed. By default, this directory is C:\Exchsrvr.
2. In Control Panel, double-click Services, click Microsoft Exchange Event Service, and then click Start.

Workaround

When the Event Service does not start and error 0x80040154 occurs, if you reinstall the Microsoft Outlook client on the computer running Exchange Server, the Event Service starts.

To successfully reinstall the Outlook client on a computer running Exchange Server, follow these steps:

1. Stop all the Exchange services and set the Microsoft Exchange System Attendant service's startup type to Disabled.
2. Stop and disable all third-party services, such as monitoring agents, backup applications, and anti-virus applications.
3. Stop the Simple Network Management Protocol (SNMP) service (if it is installed).
4. Restart the server.
5. Reinstall the Outlook client on the server.
6. Change the Microsoft Exchange System Attendant startup type back to Automatic.
7. Start all Exchange Services manually except for the Microsoft Exchange Event Service.
8. Start the Microsoft Exchange Event Service manually.
9. For any services that were disabled in step two, change the startup type to their previous values. Start any services that you manually disabled.

For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base: