No Man’s Sky has evolved over many years, so older profile directories can contain naming conventions that differ from current saves. That makes destructive cleanup risky. Archive the whole NMS directory before renaming or moving anything, and keep Microsoft Store WGS data separate from normal desktop .hg files. A future game-specific tool should identify the exact generation and container before writing; Phase 23 only documents the storage and backup boundaries.
Choose the correct backup boundary
For No Man's Sky, the researched PC save location is Windows: %APPDATA%HelloGamesNMS
Microsoft Store: %LOCALAPPDATA%PackagesHelloGames.NoMansSky_bs190hzg1sesySystemAppDatawgs | macOS: $HOME/Library/Application Support/HelloGames/NMS/ | Linux / Steam Play: Steam Play: <SteamLibrary-folder>/steamapps/compatdata/275850/pfx/. The known save file or folder pattern is save*.hg
mf_save*.hg (current/metadata family; older installs may contain storage*.hg names). Copy the entire NMS profile directory, including metadata companions, before editing or migrating. For Microsoft Store, preserve the WGS container separately. Copying the complete documented save boundary is safer than selecting one visually obvious file, because companion metadata, indexes, backups, or multiple slots can be required together.
Make an offline copy before changing anything
Close the game first, wait for the active launcher to finish writing, then copy the save data to a separate folder that the game and sync client do not watch. Label the copy with the game, storefront, profile, and date. Documented launcher context: Steam, GOG Galaxy, Microsoft Store / Xbox app. Desktop storefront files and Microsoft WGS containers are different migration surfaces. Older installations can also contain legacy storage*.hg naming.
Account for cloud saves
Storefront cloud support can synchronize the same profile. Cross-platform/cross-save features should be treated as service workflows rather than proof that arbitrary local files are byte-compatible. Before restoring an older backup, decide which copy should win. If the game or launcher starts while an older manual copy is in place, synchronization can replace it before you confirm that it works. Keep the untouched backup outside the live save path until the restored progress has been opened and saved normally.
Restore without changing format assumptions
No Man's Sky uses profile-scoped .hg save records. The Microsoft Store/Xbox app build uses WGS instead of the same visible Steam/GOG-style files. Compatibility note: Older 2016/2017 file naming and current save naming can differ. Do not rename historical .hg files blindly without retaining the originals. Restore into the matching storefront/profile context whenever possible. Do not rename a save extension, move a folder into a different container type, or assume a console/mobile copy is equivalent unless a tested migration path specifically says so.
Recovery fallback
If an older save is not listed, first preserve every .hg record and compare modification times. PCGamingWiki documents historical storage-to-save rename cases, but any rename attempt should be reversible. If the restored copy fails, put the untouched original back first. Then compare location, account/profile, cloud state, and the full directory structure before trying a different backup. The objective is reversible recovery, not repeated destructive experiments on the only copy.
Verification context: Windows/macOS/Microsoft Store/Steam Play locations and historical .hg naming notes were reviewed against current PCGamingWiki coverage.