Avast sheilds down after update of other programs such as-windows live movie mak

Had this also on my other computer that is running on xp. Did a clean re-install and fixed it.
This time my wife did an update on hers and exactly the same-lost the avast anti virus pro.
Non of the fix helps and a clean re-install on this one also only gets so far through the instal and fails.
This computer is a HP and running windows 7. Could it be blocking it? Not getting any message to say anything is blocking it.
Could i have a definate link to a clean re-download.
Thanks. ???

Did you (or your wife) use Windows System Restore?

Never done a system restore on this computer which is running on windows 7.my wife was doing a home movie using windows live movie maker and it said it needed to update so she did an update and then after that she noticed that avast was turned off and not responding to the fix now option.But not sure if avast was already off before the update.
Tried downloading it again but it only seems to get so far through the instalation and then says it failed to complete the instal.This computer is a HP and i think it came with windows defender or its own antivirus and wondering if it is blocking the Avast setup.

I did a system restore last week on my older xp pentium which probably caused that one to loose avast but i just ran the setup again as i still had it and then added our current licsense and thats fine.Only thing there was it had a heap of updates to do as it was an earlier version.Could not find a download for Avast pro-home use so downloaded the free trial but as mentioned it doesnt want to complete the setup so i have now deleted avast and ready for a clean re-instal of the latest edition.Trying to see where to disable this windows defender or whatever it is called. If it was my xp i wouldnt have a problem.
Any suggestions. Thanks.

Is there any *.mdmp in this folder? C:\ProgramData\AVAST Software\Avast\log

In theory, there is no conflict between Windows Defender and avast…

  1. Download avast! Pro Antivirus: http://files.avast.com/iavs5x/setup_av_pro.exe
  2. Follow instructions: http://www.avast.com/uninstall-utility
  3. Reinstall avast! with the downloaded installer from point 1.

Thanks again for your help.
It all seems to be ok again.The previous downloads i had been trying were not giving me any option to enter my license key but then i found another Avast exe on my other computer and that one did and gave me an option to enter my key shortly after the setup started and then the setup completed.
I was even having trouble getting back here to the forum but now i have also found my confirmation email from when i last paid in september which still has my key and other links.
Many thanks.

You’re welcome.