Which non-google email domains can edit google sites as admins

google-sites

I set up a google sites site.

I added some people to administrate it.

I notice that one guy whose email address is his own domain like tim@blob.com it lets me add his email address.

Another person that's gary@hotmail.com it lets me add him

But then when I try to add sarah@msn.com it says "Sorry, you cannot share with sarah@msn.com because they do not have a Google Account."

Well, how does it know whether tim@blob.com has a google account. And why does it have no problem with gary@hotmail.com?!

Best Answer

When creating a Google account, one can use a non-google email address.

If a person's non-google domain email address could be added to administrate a google sites site, it was because they created a google account with that email address.

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