Monster Hunter: World keeps its main Steam PC progress in SAVEDATA1000. Because the file sits under an account-specific Steam userdata tree, the account context belongs in the backup record. Copy the file outside Steam before major changes and keep multiple dated revisions rather than relying on cloud synchronization alone. A future editor must handle account/profile semantics explicitly; Phase 23 only documents where the file lives and how to preserve it safely.
Start with the least destructive explanation
When Monster Hunter: World progress appears missing, first verify the active PC location: Windows: <Steam-folder>userdata<user-id>582010remote | Linux / Steam Play: Steam Play: <SteamLibrary-folder>/steamapps/compatdata/582010/pfx/. Expected files/folders: SAVEDATA1000. Many apparent save failures are actually profile, storefront, path-redirection, or cloud-selection problems rather than damaged game data.
Preserve every surviving copy
Copy SAVEDATA1000 to a dated location outside Steam userdata. For extra context, record the Steam account/ID that produced the file. Before renaming, moving, replacing, or opening candidate backups, copy them outside the live directory. Do not use the only surviving file as the test specimen for repair or editing.
Check launcher and cloud state
Storefront context: Steam. The save is under Steam userdata, not the Monster Hunter: World installation directory. The numeric user folder identifies the Steam account context. Cloud notes: Steam Cloud/remote storage is part of the normal PC workflow. Manual backups are still valuable because a damaged local revision can also synchronize. A sync client can reintroduce an older or newer version after a manual restore, so recovery work should keep local and cloud copies conceptually separate until the wanted progress is confirmed.
Use format and compatibility clues
The Steam PC profile uses the SAVEDATA1000 file under app 582010 remote storage. The file contains account/profile progress and should be treated as user-associated data rather than an anonymous portable save. Third-party save transfers often need Steam-ID-aware handling. This Game Hub does not claim that a SAVEDATA1000 file from another account is directly portable. If the file exists but is ignored, compare the complete directory structure, slot/profile naming, game edition, mods/DLC, and any companion metadata. Do not assume an extension change or generic checksum tool can repair a game-specific container.
Game-specific troubleshooting
If progress is missing after a cloud conflict, preserve both the current remote/local file and any backup before trying replacement. Avoid repeatedly launching the game while deciding which copy is authoritative. If a known-good backup works, preserve it and create a fresh in-game save before further experiments. If no copy works, prefer read-only inspection and source-backed game-specific tooling over repeated writes.
Verification context: The Steam userdata path was reviewed against current PCGamingWiki coverage. SAVEDATA1000 naming is corroborated by long-running Steam/Nexus backup references.