I know that this is not recommended, having differing versions on the same PC.
However this has not caused a problem previously.

I have been trying to debug a problem with a lisp file and wanted to test it on an older version. While the program opens and displays the 'grey' screen It will NOT open a drawing.??????

Hi Steven,
Yes, sometimes when you install the new version, the previous one does stop working.
Try to reinstall the previous version, it should fix this issue.

Hi Quan,
I'll give that a try