This is often caused by attempting to connect to an Access database
using OLE-DB (e.g. Provider=Microsoft.Jet.OLEDB.3.51;) without having JET
Microsoft.Jet.OLEDB.3.51 is a very old version, and we have Microsoft.Jet.OLEDB.4.0 installed on our servers, in order to fix the error, please update
Provider=Microsoft.Jet.OLEDB.3.51 to Provider=Microsoft.Jet.OLEDB.4.0 from your database connection string.