The mail server has been working great for months now and we rebooted the server last night and now it won't start.  The following is the error that shows up in the event logs.

Please advise!

-------------------------------------------------------------------
Event Type:    Error
Event Source:    ArGoSoftMailServerNet
Event Category:    None
Event ID:    0
Date:        5/16/2008
Time:        11:41:44 AM
User:        N/A
Computer:    U15274182
Description:
Service cannot be started. System.Data.SqlClient.SqlException: Timeout expired.  The timeout period elapsed prior to completion of the operation or the server is not responding.
   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj, UInt32 error)
   at System.Data.SqlClient.TdsParserStateObject.ReadSni(DbAsyncResult asyncResult, TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParserStateObject.ReadPacket(Int32 bytesExpected)
   at System.Data.SqlClient.TdsParserStateObject.ReadBuffer()
   at System.Data.SqlClient.TdsParserStateObject.ReadByte()
   at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlCommand.FinishEx...

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Have you tried opening up Service Manager and starting the service manually?

Here's a question for you: If you look in the _logs directory, C:\Program Files\ArGo Software Design\ArGoSoft Mail Server .NET\_logs for example, when the service starts up, you should see the following entries when everything starts like it should:

[SYST XXXXXX 09-06-09 00:13:14] Resetting outbox
[SYST XXXXXX 09-06-09 00:13:14] Resetting POP/IMAP Before SMTP database
[SYST XXXXXX 09-06-09 00:13:15] Resetting lockout manager databases
[SYST XXXXXX 09-06-09 00:13:15] Removing expired records from the lockout manager database
[SYST XXXXXX 09-06-09 00:13:15] Removing old records from the address verification cache
[SYST XXXXXX 09-06-09 00:13:15] Removing expired records from DNS Cache
[SYST XXXXXX 09-06-09 00:28:13] Resetting outbox
[SYST XXXXXX 09-06-09 00:28:13] Resetting POP/IMAP Before SMTP database
[SYST XXXXXX 09-06-09 00:28:13] Resetting lockout manager databases
[SYST XXXXXX 09-06-09 00:28:13] Removing expired records from the lockout manager database
[SYST XXXXXX 09-06-09 00:28:13] Removing old records from the address verification cache
[SYST XXXXXX 09-06-09 00:28:13] Removing expired records from DNS Cache
[SYST XXXXXX 09-06-09 00:28:13] Removing expired records from autoresponder cache
[SYST XXXXXX 09-06-09 00:28:14] Removing expired records from greylisting database
[SYST XXXXXX 09-06-09 00:28:14] Starting the imap service at 70.89.127.76:143
[SYST XXXXXX 09-06-09 00:28:14] imap service started
[SYST XXXXXX 09-06-09 00:28:14] Starting the smtp service at 70.89.127.76:25
[SYST XXXXXX 09-06-09 00:28:14] smtp service started
[SYST XXXXXX 09-06-09 00:28:14] Starting the pop3 service at 70.89.127.76:110
[SYST XXXXXX 09-06-09 00:28:14] pop3 service started
[SYST XXXXXX 09-06-09 00:28:14] Starting the delivery service
[SYST XXXXXX 09-06-09 00:28:14] Delivery service started
[SYST XXXXXX 09-06-09 00:28:15] Remoting Server started.  Listening on port 6060
[SYST XXXXXX 09-06-09 00:28:15] Connection monitor started.  Interval is 30 minutes.

I found that if you're using anti spam tools and you see a lot of spam traffic, the DnsCache table will be slow to respond when the service starts up and cause the time out. The logs showed it stopping at:

[SYST XXXXXX 09-06-09 00:13:14] Resetting outbox
[SYST XXXXXX 09-06-09 00:13:14] Resetting POP/IMAP Before SMTP database
[SYST XXXXXX 09-06-09 00:13:15] Resetting lockout manager databases
[SYST XXXXXX 09-06-09 00:13:15] Removing expired records from the lockout manager database
[SYST XXXXXX 09-06-09 00:13:15] Removing old records from the address verification cache
[SYST XXXXXX 09-06-09 00:13:15] Removing expired records from DNS Cache
[SYST XXXXXX 09-06-09 00:28:13] Resetting outbox
[SYST XXXXXX 09-06-09 00:28:13] Resetting POP/IMAP Before SMTP database
[SYST XXXXXX 09-06-09 00:28:13] Resetting lockout manager databases
[SYST XXXXXX 09-06-09 00:28:13] Removing expired records from the lockout manager database
[SYST XXXXXX 09-06-09 00:28:13] Removing old records from the address verification cache
[SYST XXXXXX 09-06-09 00:28:13] Removing expired records from DNS Cache

I have run into this problem this problem twice now. The cause is pretty simple, the DnsCache table isn't indexed and it's not getting cleared out often enough.

To prevent this, I created a Scheduled Task in Windows to run everyday and clear out the cache. The scheduled task uses the following command line:

"c:\Program Files\Microsoft SQL Server\90\Tools\Binn\OSQL.EXE" -S .\SqlExpress -d MailServerData -E -Q "delete DnsCache Where Expires < GetDate()"

Note: This may not work quite as written as I have attached the MailServerData.mdf to my instance of SQL Server 2005 and this is not the default scenario when ArgoSoft Mail Server .Net is installed and if you attach the database to the SQL Server instance, you have to dettach the database when you upgrade.

"c:\Program Files\Microsoft SQL Server\90\Tools\Binn\OSQL.EXE" -S .\SqlExpress -E -Q "sp_attach_db @dbname='MailServerData', @filename1='', @filename2=''"

I hope this helps.

Thanks!
Rory