The 64-bit system encountered a problem where Microsoft. Jet. oledb.4.0 was not registered on the local computer.

Used last year.. Net program. After changing to a 64-bit system this year, the program runs and throws an exception: Microsoft is not registered on the local computer. jet. oledb.4.0 provided the program. After a long time, I did not know why. Then I searched for it and found that the solution to the problem was so simple:

Solution:

Compile the project and specify the target platform as x86. No CPU can be used.

Project properties-> Generate-> Configuration Manager-> platform-> click the any CPU tab-> Create platform-> x86

(Visual Studio 2010 is: Project properties-> Generate-> General-> Target Platform-> x86. The Express version does not have the target platform selection function. Qianyi network editing note)

Web applications can also be solved as follows:

In the corresponding IIS application pool, select "Set default properties of application pool"> "general"> "enable 32-bit application" and set it to true.