I checked in as advised by you and everything was OK, so I decided to download Avast from the web site as indicated in your last reply. This was done and then I switched the PC off and restarted it and the start menu would not work, although the Blue Square was not showing. I have now deleted Avast once again and everything seems to be working, do you advise that I go back to my original Windows 7, if so which is the best method of doing this. Thanks for your assistance.
Thanks for the update.It seems like Avast latest build isn't good either.Windows 10 has a inbuilt anti-virus called Microsoft defender which isn't that good but OK so even if you remove Avast your system is protected by that.If you are a safe browser then i suggest you keep on using windows 10 with the Microsoft defender anti-virus.Please try the following to check windows 10 file integrityClick on start then type CMD that show cmd in the list right on it and click on run as administrator that will open command prompt in that type sfc /scannow (there is a space between sfc and /scannow there is no space between / and scannow) Then press Enter. That will check the operating system file integrity.Once the scan is done see if it shows any message that errors found and fixed or cannot be fixedIf you are not comfortable using the PC with microsoft defender anti-virus then we can go back to windows 7 to do that i need to know the following1.Let me know the full model of the PC like Pavilion DV 67842.When did you do upgrade to windows 10?3.Do you have back up of the files you needed in a external hard drive?Sincerely,John
Thankyou for all your help, at the moment I will stick with windows 10, I got a message that Windows Defender had stopped Malware, so it could well be OK.