When I go into my Windows Mail program, I can see that I added my gmail account but its content isn't synced with the Windows Mail program.
IMAP is enabled in Gmail.
It says 'Nothing has arrived yet' tho I got plenty of mails in my gmail account
Hmmmm.....step 3 worked for me. If you've made all the Gmail account setting changes, remove your gmail account from the Mail App, then add it back in and see if syncing occurs.
Did you set the account up manually or did the app automatically enter the server details then ask you to confirm that you wish to connect the Google account by asking you to log in to Google?
Is sync mail turned on?
If you manually set up the account did you create an app specific password?
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