I have used this type of connection string.. I hope have some idea how can write the Connection string.
Data Source=Your system Name or You can used .[dot];Initial Catalog=Database Name;Integrated Security=True
Sql Authentication
<configuration>
<connectionstrings>
<add name="MyDbConn">
connectionString="Server=MyServer; Database=pubs; User Id=MyUser; password= P@ssw0rd"
providerName="System.Data.SqlClient" />
</add></connectionstrings>
</configuration>
for more information check this link
http://msdn.microsoft.com/en-us/library/ff648340.aspx[
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