Invalid File Signature

Avast Free Antivirus / Premium Security
1

Hello all,

I’ve read various Posts and replies to the subject of Invalid File Signature problems. I have as of yet read of a solution. I’ve been using Avast Free for several years now and never have had a problem. BUT…(there is always a but) now Avast does not install the updates. I started yesterday. I have been using V5 since the program asked to update. Now I have uninstalled it reinstalled the “Newest Version” rebooted and no luck still the same message. I am not going to pretend to be computer genius because I am not but. So please help if you can.

Thanks in advance,

Cheeky Monkey

2

I suggest an installation from the scratch (are you still using version 4.8?):

  1. Download the latest version of avast! Uninstall Utility and save it.
  2. Download the latest avast! version and save it.
  3. Uninstall avast from Control Panel (if possible). If, for any reason, you can’t run it, try booting in Safe Mode and doing it from there. Anyway, boot after that.
  4. Run the avast! Uninstall Utility saved on 1. If, for any reason, you can’t run it, try booting in Safe Mode and doing it from there. Anyway, boot after you’ve run it.
  5. Install avast! using the setup saved on 2. Boot.
  6. Register your free copy or add the license key for Pro.
  7. Check and post the results.
3

I followed these steps but am still getting the “invalid file signature” message and can’t update my definitions!

4

Did you follow them exactly, including the boots?

5

I have the same problem, I have been using avast for a long time, I had to change my hard drive and now cannot update