What was done to fix it the last few times?
I saw one where removing McAfee seemed to help, not sure about the most recent one, what was done to fix it then?
Can you provide some specs pleasae?
What OS, 7, 8 or 8.1?
Make and full Model number of the computer.
How much ram, how big is the hard drive?
How much free space on the hard drive?
What anti-virus or are you still using Windows Defender (which is okay, it's what I use too). If so, is it up to date with definitions?
Have you installed all Windows Updates?
Possible it could be malware but let's hold off on that for a bit.