There are some helpful information in this link that you should review to troubleshoot your issue. Please be sure to run the Stinger scan which is included to see if it finds anything.
You might also want to try to run the McAfee Virtual Technician found at the top of this page under Useful Links under Technical Support. MVT will scan your computer for any McAfee related issues and if it finds any it will attempt to fix them for you.
I didn’t get a clear picture of your issue, however it seems that McAfee scan get stuck on a particular file and computer will freeze at that moment. Am I right?
I can’t understand what you meant by “unable to switch on McAfee checker”. Do you mean Real-Time scan is off?
Could you please be more specific with exact error message from McAfee?
To have a clear picture of your issue, kindly reproduce the issue by initiating the scan again and take a Screen shot at the stage when scan gets struck.
(To take a screen shot: Push the “Prt Scr” (Print screen button) once on the top right of your key board > open Ms Paint > go to edit on the top and select paste > save the file and attach to the post)
As well, kindly update us with the following details:
Operating System: (Windows XP/ Vista / Windows 7)
Browser Version: (IE 7 / IE 8 / IE 9 / Firefox / Google Chrome)
McAfee Product: (Total Protection / Internet Security / Virus Scan / McAfee Security Scan)
Sorry for no getting back sooner.
The problem I find that when I start up my P.C. I notice it's alot slower than normal, at that point I supected something wrong. I did a Malware sweep and after 19 minutes the computer freezes and I am unable to use my mouse or keyboard so I left with no choice but to pull the battery out of the laptop and reboot the p.c. from the start. I did thing a number of time and each time it freezes. I even treid the various "Safe" modes and again it freezes after 19 minutes.
After those attempts I did a Mcafee sweep and everytime I hit the "Full Sweep" it freezes on 14% and moves no further and again my mouse freezes and the keyboard don't work. and again I did "Safe Mode" and again it freezes at 14% the only way to make it work is to pull the battery out.
I don't think I will be able to do a "Print Screen" because when these things happen the mouse and keyboard is frozen.
It working now and again just now I did another sweep and the same thing happen, I am worried that whatever it is on my P.C. it's running in the background and I am unable to check it.
As for the "Unable to turn on the Mcafee checker" I meant Real Time Checker. It turn Red so everytime I tried to turn it on to green it turns back to Red again.
I have managed somehow to update the window software package "patches" after a few goes but the auto Windows upgrade was turned off and again I was unable to turn the latest update alert on, it keeps swtching off.
My P.C. Mcafee package is "Total Protection", my operating system is Windows 7 and the Firefox is the latest on and my IE is the latest version.
If it is a malware problem.You could try to run Rkill from bleepingcomputer.com.Reboot and start in safe mode with networking.Then go to this link and download 1 of these versions of Rkill and save to desktop.
make sure you read the page before downloading.After Rkill has completed do not reboot.It should have stopped any running malware processes.If you have any that start up in safe mode.Then run a full scan.
Update malwarebytes and run and also try to run Mcafee again.See if they complete.
Lopsidedbunny, since both McAfee and Malwarebytes' Anti-Malware’s scan stuck while scanning on your computer, I suspects there may be some errors with hard disk or a corrupted file may be culprit.
To fix the issue with Real-Time Scan is off issue, go to http://mvt.mcafee.com and follow the prompts to install and run McAfee Virtual Technician. If MVT discovers any problems, allow it to repair those problems and attempt to enable Real-Time Scanning again.
If your status still shows that you are not protected, Download and save the utility from the link below to your desktop:
Double-click the oas-disabled-fix.cmd tool.
NOTE: Windows Vista and 7 users should right-click oas-disabled-fix.cmd and select Run as Administrator.
If you receive the error StopService: Unable to open service McShield via SCM (5), press CTRL+C to terminate the process. You will be prompted to terminate the batch job. Type Y and press ENTER. Run the oas-disabled-fix utility again.
Restart your computer and manually update McAfee. Ensure that McAfee Security Center shows that Real-Time Scanning is enabled.
You can once run the Stinger Scan, this tool detects and removes threats identified in the "List Viruses" icon in the Stinger application. Kindly read the instruction how to use the Stinger Tool before you execute the scan.