Error opening Project 2007 file after using project 2010

[Jio]

This is the second time I'm experiencing this problem.

Created a file (say Rev 1) in Project 2007 at work and took it home and updated it using Project 2010. When I finished updating using Project 2010, I saved the file in Project 2007 format. Came to work the next day, opened the file using Project 2007 and did a "Save As" so that I have another revision of the file (Rev 2).

After updating Rev 2 in Project 2007 I closed it but when I came to work the next day I couldn't open Rev 2 file again either in Project 2007 or 2010. This has happened to me with 2 different files.

The error message I get is

An unexpected error occured during command execution.

Try the following:

• Verify that all argumen names and values are correct and are of the correct type.

• You may have run out of memory. To free up available memory, close programs, projects, or windows that you aren't using.

[EINSTEIN_007]

It seems to me that it has to do something with invalid characters in the file name of the timeline. Or it could be anything from an '&' to two concurrent spaces, mulitple '.' or even a dash (-). Stick with single spaces, letter and number combinations and you should be fine. The problems arise based on how the file has been opened.

[Jio]

I tried changing the file name to something very simple and still no luck in opening the file.

[cynthiani]

You could try the official microsoft project 2010 help section, they have some good technical assistance documented which helped me a lot. Hope it helps!