If you are using linked servers and encounter the following error:
OLE DB provider "SQLNCLI" for linked server "SRV_2000" returned message "Query timeout expired".
check your remote query timeout setting.
To do it execute this query:
sp_configure 'remote query timeout (s)'
or go to:
(if you're lucky enough to still be using SQL Server 2000 Enterprise Manager)
(if you have to use SQL Server 2005 Management Studio, that failed to accomplish such an easy task - not being worse that Enterprise Manager - I'll rant about this more someday)
It is also worth remembering that if you are executing a remote query in a step of a job and this fails because of the timeout, the step will be written to job's history with status 'Successful':
Executed as user: DOMAIN1\sqlagent2005. OLE DB provider "SQLNCLI" for linked server "SRV_2000" returned message "Query timeout expired".
[SQLSTATE 01000] (Message 7412). The step succeeded.