First double-click the taskbar icon to open SecurityCenter
Click Navigation (top right)
Click General Settings & Alerts (left)
Click Access Protection to expand that section
Uncheck Access Protection and click Apply
To see the folder you will have to go to any Windows Explorer (internal) page (example: My Computer) and go to Tools/Folder Options/View and check 'Show hidden files and folders' and click Apply and OK.
Close and reopen Windows Explorer for that to take effect.
Leave SecurityCenter open on your desktop because you should re-enable Access Protection after the following steps.
Go to C:\ProgramData\McAfee\VirusScan\Quarantine and click Edit/Select All
If you are using XP so the path is different from what I posted above
C:\Documents and Settings\All Users\Application Data\McAfee\VirusScan\Quarantine
Don't forget to delete only the contents of that folder, not the folder itself.
Hint to make it quick click the Edit button and then "Select All"
Then right click any of the shaded area and click Shift and Delete simultaneously.
OK any prompts and although it may take some time it will eventually delete them all completely, bypassing the Recycle Bin.
Some may not go so you may have to experiment with blocks of a fewer amount but if you disable Access Protection first they should all be deletable at once..
That should stop the endless spinning when you try to open that section of SecurityCenter.
Re-enable Access Protection as mentioned above and click Apply and then exit SecurityCenter.
Unless you want to check Quarantined and Trusted Items again to see if that has improved matters of course.
By the way the vast majority of items that end up there are simple cookies and you may wish to tell VirusScan to ignore those in future.
Click Virus and Spyware Protection
Click Real Time Scanning
Go down and uncheck the Tracking Cookies.
It's optional of course.
I hope you understand this as I was copying and pasting bits of it from other threads I had posted in, sorry. ;-)
Amended post to make it a little clearer, hope it worked.