Moving MekHQ Campaign Files between versions - MegaMek/megamek GitHub Wiki

Important: MekHQ Campaign Update Instructions

It is critical to follow these steps to ensure the integrity of your MekHQ campaign when updating between versions. Failure to follow these steps can result in the corruption of your campaign file.

Treat each release as stand-alone; Copy, never Move your data forward from older versions. MekHQ is NOT backward compatible.

1. Complete all ongoing contracts in your current campaign, save, and exit the program.
2. Make a backup of your campaign and custom files. This is a critical step to prevent data loss!
3. DO NOT COPY MegaMek saves or any preference file from a different version to avoid compatibility issues.
4. Update MekHQ to the latest version. NEVER overwrite the existing folder; always keep each version in its own folder.
5. In the new version, load your save file in MekHQ and advance the game by one day.
6. Re-save any custom presets to ensure they are updated with the new version's settings.
7. Exit MekHQ and restart the application to complete the update process.

Following these steps will ensure that your campaign data initializes correctly and avoids potential issues. This process is essential for maintaining campaign stability.