What can I do to prevent this type of error messages occuring? Theese errros
are coming basicly from readonly database transaction. One part of our
massageboard on IIS. What causes this erros to occur?  There is quite a lot
of insertrs and updates happening at the same time users are reading thos
message board pages.... But this page is read only.

Transaction (Process ID 125) was deadlocked on lock resources with another
process and has been chosen as the deadlock victim. Rerun the transaction.

TLehtinen wrote:
- Minimize yout transaction duration - do not leave any transactions
open on a client - BEGIN TRAN... Exec T-SQL... COMMIT TRAN as quickly as
possible
- When you delete, insert or update from tables make sure to access
tables in the same order in all procedures
- Use Profiler to help determine your long running SQL statements - add
indexes where needed to address performance concerns
- If all else fails, consider using a NOLOCK hint on your SELECT
statements, assuming your application can deal with the possibility of
dirty reads

Here's more information:
http://www.sql-server-performance.com/deadlocks.asp

expectations for SUM query on 50+ million rows
Deadlocks "again"
How to "Grant" a Trigger ???
IN clause with comma seperated values in select query
Internal SQL Server error
Management Studio Question....
what kind of index to use in this situation.
Page coruption
Stored procedures in master database SQL Server 200/2005
Add User to Log-Shipped Database