After I updated to ImageEn 7.5 all of my projects compiled as Win64 produced exceptions with file IO. For days I could not determine what was causing the problem. I finally found that the projects with an older ielib64.dll file IO failed. As soon as I replaced the ielib64.dll with the version shipped with 7.5 the IO exceptions no longer occurred.
When developing projects I generally place the ielibXX.dll's in the projects exe folder. If you are seeing file IO exceptions, replace the old dlls with the new dlls.
I have not seen this problem in the past, so perhaps there should be some code in ImageEnIO.pas to check the version number of the dlls so that a message is shown if the version is incorrect. This will solve a lot of headaches by developers. Meanwhile just use the most recent dlls with each version of ImageEn.
The dlls are found in the imageen source folder in the DLLs folder.