Natshal84;
Greetings! Thank you for the info you have provided here. I too, was having problems with the 'AECMGDREVERSE.dll' ARX Command giving me an Exception Error each time I started AutoCAD Arch 2018. After reading yours, as well as a few other posts regarding Exception errors, I turned off my Firewall as well as my Norton Antivirus (All done through Norton) for one hour. I then cleaned my registry with Norton Tools, then rebooted the machine. Once back, instead of
uninstalling all of the AutoCAD programs, I just told the AutoCAD dialog to 'reinstall'. (With fingers crossed to see what that would do!) Once AutoCAD had finished updating, I clicked the START AC desktop Icon and held my breath. IT WORKED! No more Unhandled Exception Error Message! Thank You and all who have contributed their knowledge to fix these problems.
Oh, one more thing. I'm using FireFox instead of Windows Explorer, would that cause any future problems??