An alternative method how fix your Wurm launcher in Windows OS. Click Start -> Programs -> Java -> Check for updates -> General tab -> Temporary Internet Files -> View -> Select Wurm -> Run or right click and select Create Shortcut -> On your desktop, find Wurm shortcut and Run -> In game launcher, click Update Pack -> Verify -> When updated Wurm -> Play. In next time launch Wurm from new shortcut, old launcher - dosen't work.