If all the application in you Windows VM have the small font problem, could you try the follow steps? Open Settings -> Display, make sure both the "Use full resolution for Retina display" and "A...
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If all the application in you Windows VM have the small font problem, could you try the follow steps? Open Settings -> Display, make sure both the "Use full resolution for Retina display" and "Automatically adjust user interfaces size in the virtual machine" check boxes are checked. If not, check them, then restart the VM. If they are all set up, try to uninstall the VMtools then reinstall it. If only the specific 3rd-party applications have this problem, and others work well, probably because these apps use customized controls. You can try to uncheck the "Use full resolution for Retina display" checkbox. VM will lost some clarity, but the small font could be solved.