SQL Server Express 2005 doesn't allow remote connections by default.
Some simple instructions for allowing remote connections can be found at ... http://www.datamasker.com/SSE2005_NetworkCfg.htm.
Also grab the free ExpressMaint console utility available at http://www.sqldbatips.com/showarticle.asp?ID=29.
It provides some of the functionality of the sqlmaint utility
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