Hello, I am Elizabeth Olsen. I am digital marketing specialist and freelancer. If you're unable to Mcafee com activate after reinstalling the software, there are a few potential reasons for this issue. First, ensure that you have completely uninstall any previous versions of McAfee from your device. Lingering remnants of previous installations can interfere with the activation process. Next, verify that you're using the correct product key during activation. Double-check for any typographical errors or accidental omissions.