Hi @Anonymous
1. Make sure you are not in the proxy environment / corporate network
2. Disable all VPNs / Chrome extensions.
3. Hit Cltr+ F5 on your power pages design studio and the Power Pages site.
If the above didn't work, please follow this article to clear the cache
Finally, restart your PC and give it a try.
Bonus: I usually use XRM Toolbox and try to connect. If it is a successful connection. Then you are all good.
Hope it helps.
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