We are having a weird issue where Mach 3 is occasionally throwing in a bunch of symbols and characters when loading a G-Code.  If you open the .NC file in notepad these bad characters are not present, they are some how only appearing in Mach 3.  Stranger yet, is that we will open a file one day and it loads fine, then the same file the next day will load with these extra characters.  We are using Meshcam to generate the g-code. Also, we've been using Meshcam and Mach 3 with the same workflow for years and this problem has never occurred in the past, it just started doing this last week.  There have been zero modifications to how we generate our code and the computer running Mach 3 is not connected to the internet or local network.

Any Advice?

if this happens even with the same file only occasionally, I would assume a hardware problem. Did you change anything on your computer or cabling? Is Meshcam and Mach3 running on the same computer? That can have many reasons.

Klaus

I suspect on a bad hardware, most probably RAM. Try to pull out RAM modules and plug them back tho their sockets.