Same thing here. Mcshield.exe is always active with varying percentages like you mention , even on an idle system. Tried increasing the swap file (I only have 512megs memory) with no success. The issue started after the updates that took place about a month ago.
Turning off real-Time Scanning basically is turning off virus protection altogether so not a wise move, however all may not be lost, although with 512mb of RAM you are really on the lowest limit in the System requirements. If you can increase memory that is the easiest and fastest way of getting the machine up to speed again.
That all said the newest version should be using fewer resources, not more. It's just that the installation has somehow become corrupted so I advise an uninstall, cleanup, reboot and reinstall from the online account.
The procedure and removal tool are all included here: http://service.mcafee.com/FAQDocument.aspx?lc=1033&id=TS100507
The issue of mcshield.exe running constantly was there just after the updates several weeks ago , along with the connect issue that affected dialup access on CompuServe , Juno , and possibly others. A McAfee tech suggested a complete uninstall and reinstall to attempt to fix the connect issue (before a Tier 2 tech told me it was a bug that had to be fixed). So , I have already done a complete uninstall / reinstall less than 2 weeks ago (9+ hours on dialup - cannot get broadband). That did not solve the mcshield.exe issue at all - it was there later the same day. MVT showed all was working correctly.
Can you all please post back your system specs :
Operating system –
Internet conn = (DSL/Wireless)
How old is the PC =
Is Windows up-to-date ?
What version of Virus scan in McAfee ?
As soon as I can find my install CD (it's in a moving box) I will try a reinstall and see if that fixes the processor-use problem. Otherwise, I am running Vista Pro with wireless on a Dell Inspiron 1720 running Total Protection 11.0 with the latest update for both Windows and McAfee.
Can you also take a screenshot of Task Manager when mcshield starts going into overdrive, and save the screenshot; wait a couple of minutes and then take another and save it. Include both Task Manager screenshots in your next post. Make sure that Task manager is showing CPU, CPU Time, Memory Usage, VM Size, and Page Faults.
When this happens on my machine I can see from Task Manager that mcshield is engaged in constant swapping to (and presumably from) the hard disk, and racking up millions of page faults. It could be that you'll be seeing the same - but perhaps not.
After four IE9 crashes while trying to add a photo I'm giving up on that. Needless to say, after about 5 minutes the page faults had only increased by ~800 from 339,411 to 340,270. I wouldn't worry about page faults until the pass 50 million on this machine. Otherwise memory usage in all departments was stable. What I did notice is that while mcagent.exe is cranking away so is one of the numerous svchost.exe (I've got 14 running at the moment). Your guess is as good as mine as to what this one is doing, but as soon as I suspend real-time scanner this svchost.exe stops using CPU too, but does not close. It might just be a file handler, but is could be a problem resulting from a windows update.
Thanks for the info, astra412. This is one of those situations where there could be any one of a number of causes, and the one I picked on looks to be non-universal. Useful to know.
You can use Process Explorer (from SysInternals) to see what services a particular instance of svchost is running., and how many threads it's created (and which of those threads is responsible for using cpu).
System is a Dell 3100 , Windows XP SP3 and all updates are up-to date. The system is 6 years old. Internet connection is dialup. VS version is 15 , build 15.0.288.
Mcshield.exe normally runs between 10 megs and 40 megs , but on the first boot after an update (DAT ones included) , it goes wild for at least 10 minutes using 150 megs to 300 megs. When it goes wild , it often is running at over 50% CPU.