This is the third time this has happened in the past couple of months:
I go to open a drawing I did with the same ACAD2011 Mechanical, and it comes up with a message saying the drawing was done with an incompatible version, mechanical commands have been disabled, the drawing can not be saved in this version of the software. If I remember right, the last two times it happened, I renamed the backup file, and deleted the bad one. However, this time, the backup file is giving me the same message.
What is going on? Is it corrupted files? Any way to avoid- they're on a network server? Never happened with old version of ACAD 6 months ago. Is there any other way to 'fix' or load the files so I can save them?