When a student builds a file with MultiSIM 9, the circuit is created as a .msm file. When the student goes home to work, they can open a .msm file with a student version, 2001 for example, but any change to the file can only be saved as a .mst file. As soon as the file is saved as a .mst file, we have not found a way to open the file with the educational version of MultiSIM 9. Is there any way to convert these files? This makes it very difficult for a student to work at home for a project between or prior to labs.
Unfortunately, the ".mst" extension is supposed to be open only by Textbook editions of Multisim. Not even a Power Pro version would be able to open it.
I'm not sure the specifics of your case, but I guess that you open/saved the circuit on your textbook edition and that converted the file extension, is that right?...
Well, as far as I know the textbook editions are meant to be 'demo' type of releases, so is limited in many features. You should be OK with a Student edition though -- which is not the one commonly found in textbooks.