AD Integration - Pre-authentication failed

[mglenney]

Looking through the Security log on our domain controller I see we have a bunch of 'Pre-authentication failure' messages. They don't seem to be affecting mail delivery because they are followed closely by a successful login. Here's are 2 entries for example:

Event Type: Failure Audit
Event Source: Security
Event Category: Account Logon
Event ID: 675
Date: 4/30/2007
Time: 12:33:56 PM
User: NT AUTHORITY\SYSTEM
Computer: XDSDC01
Description:
Pre-authentication failed:
User Name: mikeg
User ID: XDSINC\mikeg
Service Name: scalix-ual/xdsmail.xdsinc.corp
Pre-Authentication Type: 0x0
Failure Code: 0x19
Client Address: 192.168.48.150


Event Type: Success Audit
Event Source: Security
Event Category: Account Logon
Event ID: 672
Date: 4/30/2007
Time: 12:33:56 PM
User: NT AUTHORITY\SYSTEM
Computer: XDSDC01
Description:
Authentication Ticket Request:
User Name: mikeg
Supplied Realm Name: XDSINC.CORP
User ID: XDSINC\mikeg
Service Name: scalix-ual
Service ID: XDSINC\scalix-ual
Ticket Options: 0x40000010
Result Code: -
Ticket Encryption Type: 0x17
Pre-Authentication Type: 2
Client Address: 192.168.48.150
Certificate Issuer Name:
Certificate Serial Number:
Certificate Thumbprint:

I recently turned on some auditing for some other stuff I was doing so maybe this was always happening and I just wasn't getting notified.

I'd like to make sure that this isn't a problem and/or that my configuration is optimized.

AD - Windows 2003 Server
Scalix - 11.0.2.17 release 1.fc5

Thanks,

MG