If by "it presses F12" you mean it opens your bag(s), this would be from the ISBoxer Addon being disabled. Or alternatively but far less common, from the ISBoxer Addon not getting generated.

You can delete the ISBoxer Addon folder from your Interface\Addons and Export again to make sure it is getting generated properly. If it is, it will re-appear when the Export is successful. If your Export does NOT say it was successful, the Addon will NOT be generated.