I have a Windows Server 2003 Small Business Server that has begun crashing more and more often. The machine does not physically power off(so I don't think it is a power supply issue), but it does not respond to any network activity. When I force a restart by holding down the power button(at 11:43:20 AM), the only relevant Event Log entry says "The previous system shutdown at 3:45:11 AM on 7/21/2009 was unexpected."

This first started about a year ago, when the machine would do this once every 3 or 4 months. Over the last month, it has started occurring more and more frequently, twice in 4 weeks, then twice in 2 weeks. 

So, two questions: 
1) Any idea what would cause crashes like this to occur? and 
2) Are there any ways to get more detailed Event Log entries from within Windows?

I have full current backups of all the data on the server, so I am not worried about data loss. I have regularly updated and scanned Symantec Virus protection managed by the domain. 

[edit] Forgot to mention, the server is Service Pack 1.[/edit]

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Here is the event log entry, in case it is useful.

```
Event Type: Error
Event Source:   EventLog
Event Category: None
Event ID:   6008
Date:       7/21/2009
Time:       11:43:20 AM
User:       N/A
Computer:   <MyComputerName>
Description:
The previous system shutdown at 3:45:11 AM on 7/21/2009 was unexpected.

For more information, see Help and Support Center at             http://go.microsoft.com/fwlink/events.asp.
Data:
0000: d9 07 07 00 02 00 15 00   Ù.......
0008: 03 00 2d 00 0b 00 90 02   ..-....
0010: d9 07 07 00 02 00 15 00   Ù.......
0018: 07 00 2d 00 0b 00 90 02   ..-....

```