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Happens OCCASIONALLY for me but if it's a constant issue for you then you might want to do some troubleshooting.

Did you migrate the user account over to the new machine? If so, you might have moved over whatever problem was causing the issue to the new machine.

You can try using another user account (or logging in as Guest, though then you might have to visit a few sites so that you can populate the "top sites" window).

If it doesn't happen with the Guest account, but always happens with your account, then it's an issue with a system file linked to your account