Cannot activate QuickBooks Desktop Pro

Issue
QuickBooks Desktop Pro 2021 software installed on Windows 10 Pro PC cannot be activated. The software accepts the License and Product codes, but online activation fails with the error below.

You'll need to update your software to access your Intuit Account here. Learn how.
The software is actually up to date, there is nothing to update, so the message is not helpful at all. The actual cause of the issue is the fact that Intuit QuickBooks is still using Internet Explorer as its internal browser, which Microsoft has now removed from Windows 10 and 11.
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