Right-click the .es3 file → Copy → Paste in the same folder. Rename it savefile_backup.es3 . This cannot be stressed enough: always back up .
To understand the importance of the ES3 Save Editor, one must understand Morrowind ’s notorious instability. Unlike modern patches, the original release was riddled with "soft locks"—situations where the game continues to run but progress becomes impossible. For example, a key character might fall through the terrain due to a collision bug, or a necessary dialogue option might fail to trigger due to a faction reputation miscalculation. save editor es3