Since other people can open the exact same map it means it is indeed a problem with your editor, or a combination of both.
Well, I can only offer you the standard procedures:
1) Restart your pc, if you haven't tried.
2) Rename/move the map file and see if it works.
3) Look for for temporary folders in your map directory (they're usually named xxxTempSc2Map I think)
If everything fails, send the map to a friend and tell him to copy/paste terrain, doodads and units into a new map of the same size and then send it back to you. You can do that by pressing CRTL+A (to select all), CRTL+C (to copy) and then CRTL+V to paste it on the new map. It'll be a bit troublesome with such a large map, but it's possible.
And do make backups periodically from now on :)
Since other people can open the exact same map it means it is indeed a problem with your editor, or a combination of both.
Well, I can only offer you the standard procedures:
1) Restart your pc, if you haven't tried.
2) Rename/move the map file and see if it works.
3) Look for for temporary folders in your map directory (they're usually named xxxTempSc2Map I think)
If everything fails, send the map to a friend and tell him to copy/paste terrain, doodads and units into a new map of the same size and then send it back to you. You can do that by pressing CRTL+A (to select all), CRTL+C (to copy) and then CRTL+V to paste it on the new map. It'll be a bit troublesome with such a large map, but it's possible.
And do make backups periodically from now on :)