I have 2 computers, both running access 2010 and loaded from the same distribution DVD. On one compter I can build and execute a database and correctly produce output file an MDE. If I then copy the db to the other and make an MDE file it works ok on that computer, but If I copy the MDE file to the original computer it will not open and reports that there are problems with the project... strange as I had not produced a "project". I have checked carefully and both configs are the same. I did notice that in the "Save and Publish" options, the compter producing the faulty MDE file does not show the *.accdb option and yet it is available on the computer that makes the MDE that works. Is this a clue ??