Been using the free version for about 4 years now and have almost convinced the other folks at work to switch to it, then they cannot activate because the server is unreachable, then yesterday afternoon at the house, the one that i always use wanted me to re-activate and it will not go to the server, even after upgrade to 2018 sp 2, I have tried all the stuff that has been listed even tried the " switch default browser to edge( knowing it would not work) ". If i cannot get the free one to work i probably will not be recommending the professional version for the other 6 computers at work, we will probably go with a different software for our CAD needs. I know i am sounding a little aggravated but i am having to download the trial version of acad in order to complete a drawing that i needed to get done.