Um.
Data Source=./SqlExpress;Initial Catalog=bongah;User Id=my user id; Password:my password
---^
Are you sure that should be a colon?
Try:
Data Source=./SqlExpress;Initial Catalog=bongah;User Id=my user id; Password=my password
"i had update question"
One thing springs to mind:
SqlConnection con = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString"].ToString());
This reads a string called "ConnectionString" from the web.config file.
<connectionStrings>
<add name="bongahConnectionString"
connectionString="Data Source=./SqlExpress; Initial Catalog=bongah;User Id=x; Password=x"
providerName="System.Data.SqlClient"/>
This defines a string called "bongahConnectionString" in the web.config file. The two names should match.
Do you also have one called "ConnectionString" that might be confusing the issue?