Nadya,
You should first return your old password, in order to start SQL Server.
Then in Enterprice manager run

Properties/Security tab

and look at

Start and run SQL Server in the following account

if you want SQL Server to run independently of administrator password set this property to

System account

>Hi everybody,
>
>I've installed SQL Server on my Windows 2000 machine on Friday. I set it to use Windows credentials. I believe, I changed Windows password after installation (since the previous password expired). Now SQL server could not be connected (gives me a 1069 Error). I don't know, what to do... I re-booted my computer in false hope, it would work, but it didn't. I've created database on Friday...
>
>What should I do at this point? Should I try to re-install?
>
>Thanks a lot in advance.