Hopefully this helps whoever is still having issues with Windows firewall blocking QuickBooks.

Even with firewall off and antivirus off I would still get the message that windows firewall was blocking QuickBooks.

On the pc holding the company file to be accessed-I reset all firewall settings to default.

Then I typed in allow application through firewall in the search box.

Scrolled through the allowed applications.

QuickBooks was an allowed application but QuickBooks version 21 was not.

Clicked on "change settings"-then clicked on "allow another app"-then hit the "browse" button and searched the QuickBooks 21 version.

I added that version to "Allowed apps to communicate through windows firewall", rebooted my system and I can now access QuickBooks.