Sorry to hear of your problems, Marlene. But I would not bother returning to V8, as I am pretty sure that V8 and V9 will behave the same. I am confident that neither TMG itself nor a particular TMG version is the problem.
In every case so far for all other users the cause of this problem always has been one of two issues:
- there is another program on your computer interfering with the file being created, or
- the file is being saved to a folder which on an external device (e.g. thumb drive) and not your main hard drive, and the program controlling that external device is interfering.
One thing I would suggest you try, create a new folder somewhere unrelated to your normal work. Maybe create that new folder at the root of your main hard drive (e.g. C:\gedfiles). Now instruct the TMG GEDCOM export to create the export file within that new folder. Hopefully whatever the interfering program is will not know about that new folder and thus not interfere.
Hope this helps,