Moving a web project from test enviroment to the web server made this error occur whenever tehre\'s an attempt to open a connection to the sql server.
We can insert
causes this error is connectionString in webConfig
Set connectionString in webConfig.
name of connectionStrin in webConfig and code behind must be same.
in web.config:
in code:
SqlConnection Connection = new SqlConnection(ConfigurationManager.ConnectionStrings["DSVUShort"].ToString());
Connection.Open();