Hi, i had the same problem and have a solution:
First you need to upgrade the OLE DB drivers, install the SQL Native Client 11.0 (available from Microsoft: Download Microsoft® ODBC Driver 11 for SQL Server® - Windows from Official Microsoft Download Center)
This is because of that support for "readonly" was released with SQL Server 2012.
After that change the provider to: SQLNCLI11.1 and you need to use ;application intent=readonly; with a [space].
applicationintent is for ODBC.
application intent is for OLEDB.