can't connect to sqlexpress

I tried connecting to sqlexpress from the command prompt and I get the following error:

Named Pipes Provider: Could not open a connection to SQL Server [53].< xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Sqlcmd: Error: Microsoft SQL Native Client : An error has occurred while establi

shing a connection to the server. When connecting to SQL Server 2005, this failu

re may be caused by the fact that under the default settings SQL Server does not

allow remote connections..

Sqlcmd: Error: Microsoft SQL Native Client : Login timeout expired.

I use WinXP . Any help with this

Thanks

Malika Senaratna
I did configure and changed everything to local system and that made it work properly.
Peng Song
Did you try configuring SQL Server 2005 Network Configuration If not, you can use Configuration Manager to enable Named Pipes.
can't connect to sqlexpress