Connection string problem

[John]

Hi

I am manually able to create a connection to my db in the vs2005 ide using
Tools->Connect to Database. In the connection I see 'Data
Source=MYSERVER;Initial Catalog=aspnetdb;Integrated Security=True' as the
connection string and 'NET Framework Data Provider for SQL Server' as the
provider. Following these settings in my code and I have used the connection
string;

<add name="Membership" connectionString="Data Source=MYSERVER;Initial
Catalog=aspnetdb;Integrated Security=True"
providerName="System.Data.SqlClient"/>

in my app's web.config file. This connection is then used by a custom
membership provider for the create user wizard. Now when I try to create a
new user in the wizard I get the following error;

System.Data.SqlClient.SqlException: Cannot open database "aspnetdb"
requested by the login. The login failed.
Login failed for user 'MYSERVER\ASPNET'.

I was able to work fine when the db was on sql express. What is the problem
and how can I fix it?

Thanks

Regards