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Create a Sheet Set
Backup and Recover Sheet Set Data Files
The data stored in the sheet set data file represents a significant amount of work, so you should take the same care to create backups of DST files as you do for drawing files.
In the unlikely event of DST file corruption or a major user error, the previously saved sheet set data file can be recovered. Every time the sheet set data file is opened, the current sheet set data file is copied to a backup file (DS$). This backup file has the same file name and is located in the same folder as the current sheet set data file.
To recover the previous version of the sheet set data file, first make sure that no one else on your network is working on the sheet set. Then, it is recommended that you copy the existing DST file to another file name. Finally, rename the backup file from the DS$ file extension to the DST file extension.