Question

I am getting the following error if I try to run the ASP.NET 4.0 website in a 64 bit machine with Enable 32 bit Applications flag set to false. (I have to set that to False, If I set it to true its working fine).
> “Could not load file or assembly ‘Common.BL’ or one of its dependencies. An attempt was made to load a program with an incorrect format.

And in the project properties the Target of Build is set to Any CPU.

Still I am getting the same error.

Can you guys please help me resolving this error. Anyhelp would be appreciated.

Thanks.
Sameer.

Answer 1

Ensure Common.BL is 64 bit. You can check this fairly easily. Check this out for help:

How to determine if a .NET assembly was built for x86 or x64?

Let’s use that as a starting point, post the results. If it is a 32 bit and you are on IIS 6, then ALL of IIS must be set to run in 32 bit mode.
If you are in IIS 7 then you can set a specific app pool to run in 32 bit mode. Ensure you compile your code for 32 bit though.