Customize menu > Preferences > Preference Settings dialog > Files tab
On the Files panel of the Preference Settings dialog, you set options relating to file handling. You also select the program used for archiving. This is where you control the options for log file maintenance. You enable Auto Backup in this dialog to automatically save your work at defined intervals.
Interface
File Handling group
Backup on Save: Creates a backup file if a file of the same name already exists. The existing file is renamed "gmaxback.bak" and placed in the gmax/autoback directory before the save occurs. The automatic backup settings are edited in the Auto Backup group.
Increment on Save: Creates a new copy of the file in the same directory whenever you save the file. The name of the new file is incremented by 1 (filename01.gmax, filename02.gmax, and so on).
Compress on Save: Saves the GMAX file in a compressed format. Depending on the details of the file, the compressed file can be as small as 1/5th the size of its uncompressed equivalent.
You can determine whether a GMAX file is compressed or not by bringing up Properties of the file in Windows Explorer. On the Contents panel, under General, you'll see whether the file is compressed or uncompressed.
Save Viewport Thumbnail Image: Saves a 64-pixel thumbnail of the active viewport when you save each MAX file. The Asset Browser reads thumbnails. Saving thumbnails adds about 9K to each GMAX file.
Display Obsolete File Message: Turns off the "Obsolete data format found - Please resave file" alert that is displayed when you load a GMAX file created in an earlier version of the software.
There is a matching "Do not display this message" check box in the alert itself, and you can also turn off the alert from there.
Recent Files in File Menu: Specifies the number of recently opened files to display at the bottom of the File menu. Range=0 to 9
Auto backup is a system that saves your work periodically. In the event of a power failure, if you have not saved your work, you can load in an auto backup (autoback) file from the gmax/autoback directory and continue working with little lost time.
Auto Backup creates auto backup files based on a time interval. The name of an auto backup file is autobakn.gx, where autobak is the main part of the name (autobak is the default), and n is an integer from 1 to 9.
For example, if you've set the system for three auto backup files at one-minute intervals, the autoback system will create autobak1.gx, and then a minute later autobak2.gx, and then autobak3.gx. At the fourth minute, the system overwrites autobak1.gx, and so on.
Enable: Enables the Auto Backup system.
Number of Autobak Files: Determines how many backup files to write before overwriting the first one. Range=1 to 9.
Backup Interval (minutes): Determines the number of minutes between backup file generation.
Auto Backup File Name: This option lets you enter an alternative name for the auto backup file. Auto backup files with a different name still have the file name extension .gx. Default="Autobak".
Log File Maintenance group
The following controls affect the gmax.log file.
Never Delete Log: Determines how long the log file is maintained. When you choose Never Delete, the gmax.log file remains on the hard disk and continues to grow.
Maintain Only...Days: Resets the file to zero bytes every set number of days as specified in the Days field.
Maintain Only... Kbytes: Resets the file to zero bytes when it reaches the size specified in the KBytes field.
Errors: Writes fatal errors to the gmax.log file instead of generating Alert dialogs.
Info: Writes general information to the gmax.log file instead of generating Alert dialogs.
Warnings: Writes warning messages to the gmax.log file instead of generating Alert dialogs.
Debug: Writes debug messages to the gmax.log file instead of generating Alert dialogs.
The type of errors covered by these four categories include maps that can't be found, missing UV coordinates, missing output directories, full disks, missing DLLs, disks to which you don't have access, invalid meshes, and obsolete GMAX files
Import Options group
Zoom Extents on Import: Zooms all viewports to scene extents after importing a file. If this is turned off, zoom extents isn't performed.
Archive System group
Program: Specifies the name and location of the program to use for archiving. The program must be independently installed on your system. You can add command-line arguments to follow the executable file name. For example, for the PKZIP program, the arguments might be:
project1.zip c:proj0?.gmax -o