This is an error than may drive you crazy when you need to connect your Oracle Database to Excel, specially when you’re connecting Power Pivot . It may be a dirver and concectors issue; plus its really simple to fix it.
Error shown is:
Couldn’t load various tables … ‘System.Data.OracleCliente’. Unable to find the requested .Net Framework Data Provider. It may not be installed.
A.- Install Oracle Drivers – InstaClient Remember to select your proper Office version (32 or 64 bits)
B.- If you have installed it already and the problem continues then you should make a little fix to the machine.config file of .NET framwork
- Open .NET Framework Folder (C:\Windows\Microsoft.NET) there you should select your version 32 or 64
- Look for the most recent version
- Search and edit machine.config file
- In the file search for the tag <DbProviderFactories>
- Now this is where’s the problem, you’ll find two close tags, one is closed the wrong way, so you’ll need to delete it : <DbProviderFactories />
Next step would be restart your computer and that’s it.