Exchange server services

Exchange 2000 logs a critical state when any of the following Services stops running:

 
Web Storage System
Message Transfer Agent (MTA) Stacks
Routing Engine
System Attendant
SMTP
World Wide Web Publishing Service* Exhange 2003 services.

If one of the service stop then exchange 2003 stops working
Micosoft exchange event
Microsoft exchange IMAP4
Microsoft exchange Information store
Microsoft echange Management
Microsoft Exchange MTA stacks
Micosoft Exchange POP3
Microsoft Exchange Routing Engine
Microsoft Exchange site Replication service
Microsoft Exchange System Attendant
　
*Exchange server 2007 services
Total 18 services:
Microsoft Exchange Active Directory Topolgy service
Microsoft Exchange Anti-spam Update
Microsoft Echange Edgesync
Micosoft Exchange File distribution
Microsoft Exchange IMAP4
Microsoft Exchange Information store
Microsoft Exchange Mail submission
Microsoft Exchange Mailbox Assistants
Microsoft Exchange Monitoring
Microsoft Exchange POP3
Microsoft Exchange Replication service
Microsoft Exchange Search Indexer
Microsoft Exchange Service host
Microsoft Exchange Speech Engine
Microsoft Exchange System Attendant
Microsoft Exchange Transport
Microsoft Exchange Transport log search
Microsoft search (Exchange)