The Arbortext 5.4 online license tool was retired last year. However, TS bulletin 172301 suggests this is now reinstated "for eligible customers". Following the link to the "Helpful Resources" page shows a new link for "Arbortext 5.4 online license tool". This link is wrong and doesn't work (it seems to be pointing to a dev/test server "supportdev.ptc.com"). The original link for the Arbortext 5.4 license tool also doesn't work. Either the tool should be reinstated, or the TS bulletin should be rewritten or retracted.
