System.BadImageFormatException

This usually happens when trying to use the Chilkat 32-bit .NET 2.0 Assembly on a 64-bit system. Download and use the x64 build for the Chilkat .NET 2.0 Framework at http://www.chilkatsoft.com/downloads.asp

Also, it’s likely that your development environment is 32-bit. You should add a reference to the 32-bit ChilkatDotNet2.dll, but deploy the 64-bit ChilkatDotNet2.dll to the x64 computer. Make sure the versions agree because the .NET runtime enforces version agreement.