Try to Deactivate and then Reactivate all the sceneries (don't uninstall or reinstall anything, is not required)
This can *possibly* related to the fact Esellerate finally closed all its services yesterday so, if you previous activation was obtained with Esellerate, it must be now redone with the new QLM/Soraco system, it has worked so far, since the Esellerate servers were still up.