Unable to create an instance of the OLE DB provider "OraOLEDB.Oracle" for the linked server "XXX". (Microsoft SQL Server, error: 7302)

There are two most common two reasons for this error

1. Registration Form

<1> Press Win+r, open the "Run" window, enter "regedit", return

<2> on the left side of the Open Registry Editor, expand by the following path:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\mssql.1\providers

Under the providers generally do not see the OraOLEDB.Oracle this item, so new this item.

Right-click on the providers to select New key and rename the newly added item to "OraOLEDB.Oracle"

<3> adds a DWORD Value to the "OraOLEDB.Oracle" key and changes the name to "AllowInProcess"

<4> change the value of "allowinprocess" to "00000001"

2. Settings for the Access interface

Right-click the Oracle interface, such as: before allow in-process check.

Unable to create an instance of the OLE DB provider "OraOLEDB.Oracle" for the linked server "XXX". (Microsoft SQL Server, error: 7302)