Do not use unsupported OLE DB providers in a DataSource
This rule analyzes data sources to determine whether unsupported OLE DB providers are being used.
For best results, you should typically use supported providers to connect to data sources whenever possible. Analysis Services was designed and tested to work with a specific set of OLE DB providers. Although other OLE DB providers are available, and the Data Source Wizard lets you select any compatible provider, the capabilities and behavior of different providers can differ significantly. This is true even for different providers that connect to the same database. For a list of officially supported providers, see Working with Data Sources in SQL Server Books Online.
For more information about performance issues related to OLE DB providers, see the section, "Optimizing the source query," in the SQL Server 2005 Analysis Services Performance Guide.