I asked this in the viz4 forum, but they directed me to this one... "No, this is an error with a network license (since the middle digit is 5; also the negative number is a clue). Please post your question in autodesk.autocad.network." Could please help me someone with this: I had a harddisk crash and reinstalled my Win2K system(SP4, excl. the hotfix that causes errors with viz4). Then I installed my VIZ4, and I get error 1.5.-5. I only use administrator as a login. Please need it fast... Nicolaas