Recommendations:
1. rename the files, removing the *.exe extension. They then should be
able to be opened ... unless of course whatever renamed the files has
damaged/changed the files.
2. find how why the files were renamed. This could be someone at your
office/home, or could be a computer virus, or some other nefarious
person or program. This change was not done "on it's own" by the
operating system.
Hope this is useful to you. Let us know.
rms