You could try to follow the steps in this http://service.mcafee.com/FAQDocument.aspx?lc=1033&id=TS100762
If no success then try
http://service.mcafee.com/faqdocument.aspx?id=TS100966&lang=en_US&prior_tid=2&An swerID=16777216&turl==http%3A%2F%2Fkb.mcafee.com%2Finfocenter%2Findex%3Fpage%3Dc ontent%26id%3DTS100966%26actp%3Dsearch%26viewlocale%3Den_US to see if it resolves the problem.
If still having problems then contact Technical Support under Useful links at the top of this page
This could be because the subs on the second PC not syncing up with your account details ,
Please check the date and time on the affected PC (from the right bottom corner)
If they are set right, please continue with the steps outlined by K3tg, from here : http://service.mcafee.com/FAQDocument.aspx?lc=1033&id=TS100966
Select the concerned subscription during the process and restarting the PC would take care of the issue.
Kindly get back to us if you encounter any issues post the fix !!!