Most users resolve this by manually scrubbing the corrupted entry from the save file using a text editor like .
ERR Site Label Detected New: <path_to_file>
Open Windows Run ( Win + R ), type %appdata%\..\LocalLow\Ludeon Studios\RimWorldWin\Saves , and press Enter .
: Mods like Multiplayer or large-scale faction expansions occasionally create "hidden" or "spectator" factions. If a storyteller tries to give a quest to or generate a site for a faction lacking physical map coordinates, the label fails.
Open your active quest log and select the broken quest labeled ERR .
: Press Ctrl+F and search for the string "ERR" . Use case-sensitive matching to find the specific "ERR: [Site_label]" entry.
While annoying, this error is rarely "game-breaking" unless it prevents you from clicking anything on the world map. If the "ERR" persists across even after verifying files, a clean reinstall of the game and its mods is the recommended "nuclear" option.