So for the past few weeks I've had the problem that I click on "signing in" on Calendar. I click on the following button:
It then looks like it is signing me into Calendar. It starts loading and then takes me to the same login page. It didn't do it in anything but the Chrome browser. Though it might happen on other browsers that I don't use so try these general settings.
Here is how I fixed it:
1. Go to Chrome Settings by clicking the 3 dots on top right
2. Click Advanced
3. Under Privacy and Security, Goto Site Settings
4. Under Site Setting, Click on Cookies
5. In Cookies section disable "Block third-party cookies"
It will look something like this:
This will now allow you to get to Calendar dashboard page.
However, I did not want to keep 3rd party cookies to be enabled, so as soon as I changed it issue came back. It's because URL/site is still calendar.com and Google is trying to set it's own cookie.
So I went back in the same sequence again added 2 more steps
6. In the same Cookies section I re-enabled "Block third-party cookies"
7. At the bottom of that page in the "Allow" section, I added "calendar.com/login" and saved it.
Solved the problem!