Cannot use Windows Authentication to connect to local Sql 2005

Hi,

I am building my workstation again, freshly installing everything.
The OS is Vista Business, 32 bit. I've installed Sql Server 2005
Developer Edition fine and applied service pack 2 successfully. It
seems to run fine, with one exception.

I can't logon using Windows Authentication. I'm a member of the Local
administrators group (as well as a Domain admin), but my domain
\username gets a logon denied error. I can logon just fine with the
sa account, but I prefer Windows Authentication.

Any ideas?
Thanks
Andy

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