Hi,
Please clarify/follow the steps bellow
What is the operating system that you use?
Windows XP: Go to Start > right click My Computer > click on Properties and on the General tab you'll find all the information, incl. any installed Service Packs.
Check the DAT Version of the McAfee Virus Scan, DAT file created Date. (McAfee Security Center-> Click in the Bottom Right Corner about  McAfee Virus scan Dat created Date and version)
Try Updating the McAfee using the Update button in the McAfee Security Center after running the MSCPRXFIX (KB Doc ID: TS100291)
http://download.mcafee.com/products/licensed/cust_support_patches/MSCPRXFIX.exe.
Run McAfee Virtual Technician (http://service.mcafee.com/MVT.aspx?MVT=1&&lc=1033&sg=TS&pt=1)
Do you experience any kind of pop-ups or Alert regarding the Virus/spyware in the computer?