There is an oddity in the way the sign in for 3D Warehouse and other features work, compared to being signed in as a Classic user. If you were a subscriber, every 28 you would need to sign out and back in again. As a Classic user you don’t have to do that, but, the warehouse and add location windows are using the subscription method for signing you in.
Which means that even though you are still signed in within SketchUp, do a sign out, and sign in again, and those features should work for the next 28 days.
By the way, you still had support until April 2021, which means you have a SketchUp 2021 license that you haven’t used yet.
There is something going on with SketchUp 2018, where I think that the URL being tested to see if you are online is not being successful. The address it checks is Google. That can be seen by the system as being an insecure site that also blocks a redirect.
See if what I wrote in these posts helps your case too:
I think this might be the issue as my instincts had isolated something like that being a cause
For example sometimes if I shutdown sketchup or login via the browser in a particular sequence the problem will go away but lately I haven’t been able to do that.
I’ll brute force the possible permutations and see if it pops
As Im not sure quite what fixed it but suspect ow was the logging into the services I record the follwoing points for any future users.
I closed down all my browsers and Sketchup.
I opened Sketchup and logged into Sketchup from the first window. Bounced to an uptodate Browser.
I logged in using loginto Trimble Direct option
Returned to Software and tried 3D Warehouse and Geo Location services successfully.
I make the point that when I was having problems I had multiple profiles open in many browsers with no particular order of closing Sketchup but seldom closing my browsers completely.
Sadly, you can do as many log ins to Trimble sites in a browser, and it won’t help you with SketchUp. Only the log ins that started from SketchUp are able to make a record of when your 28 days started.
In other news, I got the license system to send you your 2021 license, in case you didn’t have it.
Ill try and flick you back an awesome template Im making for sketchup that allows Archicad users to draw in sketchup in the same layer configuration they use in Archicad. might help some interop users.
Im thinking of trying to sell it on the 3D warehouse so that will be an interesting