How do I fix missing co-op inventory or wiped progress?

Steps

1. Have the host and clients update to Update 6 or later.
2. Load the host's intended campaign save and rejoin with the affected client character.
3. Check the client's inventory and quest tab after the updated session finishes loading.
4. If data is still missing, report the build, host save and client state to NerveLabs; do not overwrite backups based on an unverified recovery trick.

Requirements / limits

• Update 6 states that co-op quests track to the host.
• Gaming Plus TV and Notebookcheck independently describe host-held campaign state and consequences that apply to the whole party.
• The changelog does not document a manual recovery procedure or guarantee retroactive restoration of data already lost before the patch.
• Update 7 touches this area twice more. Under Fixed, NerveLabs list a memory leak in the inventory menu; under Updated, that co-op allies can strike summons without retaliation, and under New, that co-op companions are visible on the compass. None of the three is a progress-loss fix, but a client on a pre-Update-7 build is running the inventory menu that leaked.
• A launch-day co-op session recorded on 17 August 2026, before this patch, shows symptoms Update 6 does not name: a looted corpse sitting in a different place for each player, a body visible to one player and absent for the other, the host's own character lying inert on the guest's screen after hosting, one player's rest advancing the other player's clock, and a rejoining guest arriving invisible with equipped clothing unequipped. Update 6 lists inventory, quest state and wiped progress. A player on the current build who still sees the other symptoms has not necessarily failed to patch.

Common mistakes

• Having only the host update while a client remains on an older build.
• Treating a client quest tab as the authority when Update 6 assigns co-op quest tracking to the host.
• Claiming the patch can recover every older lost item or quest state.

Still unverified

• Do the position and visibility desyncs recorded before Update 6 still occur?Not verifiedThe only recording of them is from 17 August 2026, launch day. Update 6 does not name them among its fixes, so their absence from the changelog is not evidence either way. One of those players also says the developer had acknowledged a desync issue; that is a player paraphrasing a statement this repository has not located, so it is recorded here rather than cited as a developer source.