PDFCreator stopped working on Windows 2008 Server

I have two windows 2008 servers with PDFCreator on them.  At some point, whether it was some maintenance or what, PDFCreator stopped working on both.  The error I get is this:

Could not load file or assembly ‘Interop.PDFCreator, Version=, Culture=neutral, PublicKeyToken=null’ or one of its dependencies. An attempt was made to load a program with an incorrect format.

Which Version of PDFCreator do you have on the servers?

Have you tried uninstalling and reinstalling the latest version?

best regards

Im running the most recent. I did try reinstalling to no avail. I ended up having to recompile my apps to run 32 bit and it seems to be working now. Not sure why it just stopped working but I suspect something in the OS was updated during a maintenance window.