Try right clicking the shield in system tray and choose update
If still no go run the MVT program in tech support link in useful links tab above
There is a manual dat update method but best first to see why auto updates fail
By the way how much ram have you and what is your Operating system and service pack?
I have tried right clicking on the shield in the system tray and the result is the same, the update spins ans spins but no update is ever downloaded. I am using windows Vista service pack2 with 2 GB of ram. I used the MVT and the first time I ran it it said my DAT was not updated, but it was unable to update it an it said update is pending. The second time I ran it MVT said there was no problems found. I tried to manually update but was unable to get that to work either.
The next thing to consider is have you any other AV installed?
Failing that uninstall Mcafeevia MCPR tool
and reboot and run Mcpreinstall
Reinstall from your account