Author Topic: Windows 7 unable to load OS after avast installation  (Read 2924 times)

0 Members and 1 Guest are viewing this topic.

Offline epictet

  • Newbie
  • *
  • Posts: 3
Windows 7 unable to load OS after avast installation
« on: August 27, 2009, 03:37:12 PM »
hi,

i just installed the version of avast available at download.com, on windows 7 RC. i selected the option for a boot scan, and then restarted the system. on restart the OS doesn't load, with the message "unable to load OS". is there anyway to remove avast, or stop the attempt to scan the boot sector so i can get into the OS?

thanks

Offline igor

  • Avast team
  • Serious Graphoman
  • *
  • Posts: 11801
    • AVAST Software
Re: Windows 7 unable to load OS after avast installation
« Reply #1 on: August 27, 2009, 03:40:08 PM »
The boot-time scan doesn't mean "scanning boot sector" - and if you get the message "Unable to load OS", it's happening much earlier than the boot-time scanner may have a chance to start... so it's hardly connected anyhow.

Offline Lisandro

  • Avast team
  • Certainly Bot
  • *
  • Posts: 67250
Re: Windows 7 unable to load OS after avast installation
« Reply #2 on: August 27, 2009, 03:41:05 PM »
Can you boot at safe mode and uninstall avast from there?
Is there any other antivirus in this computer?
The best things in life are free.

Offline epictet

  • Newbie
  • *
  • Posts: 3
Re: Windows 7 unable to load OS after avast installation
« Reply #3 on: August 27, 2009, 03:56:27 PM »
this is directly related to avast somehow, because beforehand my system ran without any trouble. i'm just trying to find a solution...

i just tried getting into safe mode, and the system asked for a boot device. i selected my main HD, and received the error "the file is missing or corrupt, system\hal.dll. reinstall another copy of the file."

is there any sort of avast recovery disk, or way to stop it from trying that initial bootscan?

Offline Lisandro

  • Avast team
  • Certainly Bot
  • *
  • Posts: 67250
Re: Windows 7 unable to load OS after avast installation
« Reply #4 on: August 27, 2009, 04:07:13 PM »
Overinstallation can solve the problem and you won't lose your programs, settings, data, files, etc.
Just choose 'Repair' installation of Windows and install 'over' the old installation.

http://support.microsoft.com/default.aspx?scid=kb;EN-US;315341
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q314058
http://support.microsoft.com/?scid=kb%3Ben-us%3B315341&x=15&y=0
The best things in life are free.

Offline epictet

  • Newbie
  • *
  • Posts: 3
Re: Windows 7 unable to load OS after avast installation
« Reply #5 on: August 27, 2009, 04:16:06 PM »
tech,

thank you for the help. i looked around online with the error message and was able to fix things.

somehow the boot sequence of my HDs had been changed in the BIOS. i just needed to set them up correctly again and everything worked fine. i don't understand how the HD sequence would have changed other than somehow through avast though, since i hadn't changed anything else on my system before that reboot.

anyway the important bit is everything is fixed. thanks again for the VERY quick replies!

Offline Lisandro

  • Avast team
  • Certainly Bot
  • *
  • Posts: 67250
Re: Windows 7 unable to load OS after avast installation
« Reply #6 on: August 27, 2009, 05:13:01 PM »
anyway the important bit is everything is fixed. thanks again for the VERY quick replies!
Good. Be used to avast forum answering speed ;)
The best things in life are free.