The 1.0 release of Valheim changed the save system, so SaveSync for Valheim was not working.
Patch note from Valheim:
[c]New save system: Splits world data across chunks to reduce how much data is serialized and written to improve performance, and is designed to be resilient against mid-write failures[/c]

We've fixed this issue. The only catch is that you'll need to do a quick migration:

  • If the save was never activated (i.e. it doesn't show up in Valheim), click Activate on it in SaveSync once first. Otherwise, skip this step.

  • Remove the old Valheim save from SaveSync.

  • Launch Valheim so it converts your local world to the new format.

  • Add that save back to SaveSync.

  • Re-share it with your friends.

Valhiem Guide: https://steamcommunity.com/sharedfiles/filedetails/?id=3792637336https://www.savesync.games/

https://store.steampowered.com/app/3832010/SaveSync_Coop_Save_Sharing_Made_Easy/