Error: Unknown Connection Option In Connection String: Attachdbfilename

Cant seem to get my connection string to work. app.config file: Copy

Thanks everyone, Kindly

Solution 2:

Template for connection string is

<addname="TrempimModel"connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;
                   database=YourDatabaseName;
                   AttachDBFilename=|DataDirectory|aspnetdb.mdf;
                   User Instance=true"providerName="System.Data.SqlClient" />

please remove '\' from the attachdbfilename attibute after datadirectoy so new connectionstring will be

<add name="PalisadeWorldDatabaseConnectionString" connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|PalisadeWorldDatabase.mdf; Integrated Security=True;User Instance=True" providerName="System.Data.SqlClient"/>

and when getting connection string use.

SqlCeConnectionCon=newSqlCeConnection(ConfigurationSettings.AppSettings["PalisadeWorldDatabaseConnectionString"].ToString());