When double clicking a .MFG file in Windows Explorer or on the desktop, a specific ArtiosCAD version should be used to open this file type.
Go to the MFG file.
Click the right mouse button and select Open with > select ArtiosCAD or click Browse and go to artioscad.exe to choose the specific ArtiosCAD version:
Select the Always use the selected program to open this kind of file check box.
Sometimes this may not work for MFG files and some other file types such as .EPS files. In such cases, try this workaround:
Type associate in the Start menu.
Choose the search result for change the file type associated with a file extension. Use the list that opens to find and manually associate the .package type with your program. It will open: Control Panel > All Control Panel Items > Default Programs > Set Associations.
Associate your .MFG / .EPS file extensions to the corresponding ArtiosCAD version.