Sign out, sign back in.
How can I sign in? I’m already signed in SketchUp, and using. Can you tell me more details please
I said sign out, then sign in. You have the ability to sign out from the help menu. I do mean sign out of sketchup …
Okay. Im gonna try this. Thankyou
I’m try this bro. But not open.
conseguiu resolver? o meu tamném esta assim. e tbm já refiz login
Don’t double post.
Sign out of SketchUp and sign back in.
I’m also having the same problem since last Thrusday 
Did you try signing out of SketchUp and signing back in?
It’s not even possible, because the page won’t load. I’ve tried it in the Internet Browser and inside SketchUp itself. Is anybody else with the same problem?
This message is appearing since last Thursday, I can’t download anything
If you can open SketchUp you can sign out of SketchUp. Go to the Help menu and sign out. Then sign in again.
IT WORKED, OMG! THANK YOU SO MUCH!!! 
You know, I said that in my second reply, make sure you read what has been said already. I know it can be missed but you could wait days for an answer that is already there.
Thank you so much 