SQL ".mdf" interface with VS2005

[Kivak Wolf]

Hey,

Not sure how to explain this. But I created a SQL server database file
called "testingData.mdf" using VS2005 and I connected to it. After I
create it, I can modify it, connect things to it such as my gridview.
However, when I preview the page in the browser, it says that some
other program is using it an it cannot. I solved the problem by
disconnecting VS2005 from the database. It showed the information
perfectly. The problem is when I reconnect to the database it gives me
this error:

Cannot open user default database. Login failed.
Login failed for user 'SOSHA\Kivak'.

(My compter's name is SOSHA and my username is Kivak)
I don't know how to fix that. However, if I just let my computer sit
for about 5 minutes, it allows me to reconnect with no problem... Is it
something that I can fix? Or do I just have to keep waiting everytime I
disconnect from the SQL database?

Thanks,
Kivak