Answer
Query FND_CLIENT_LOGON_TAB directly and use the DIRECTORY_ID and OS_USER columns to find the specific stale session record for the affected account/user combination, then delete that row and commit — for example: DELETE FROM FND_CLIENT_LOGON_TAB WHERE DIRECTORY_ID = '<account>' AND OS_USER = '<domain\username>' AND PROGRAM = 'Ifs.Fnd.Explorer.exe'; COMMIT;. This clears the stuck 'already logged in' state immediately, rather than waiting for it to clear automatically after an HTTP session timeout.