Windows 8 failed to start after installing Avast 8.0.1483.72

[itsmechlark]

Hi,
I have a problem with Avast 8.
First, it happens to when Avast 7 updated to Avast 8. I turn on my PC after a shutdown Windows unable start, restarted twice. After the last restart Windows,  its started the Windows Diagnosis and Recovery and failed to repair. When I uninstall Avast at Windows safe mode and start Windows in normal mode, it start normally.
Second, it happens when I try to install again the Avast 8. When I restarted my PC, Windows failed to start. After Windows restarted twice, its started again the Windows Diagnosis and Recovery but recommended me to restore. When I restore before I install Avast, Windows start correctly.
I added a link that maybe it can help:
https://docs.google.com/file/d/0B8ylnmxsY33vTXFkUm5lczRBTkU/edit?usp=sharing

Thank you.

[true indian]

Run the uninstaller for any AV's you used prior to avast from here to remove remanents: http://singularlabs.com/uninstallers/security-software/
1. Download avast! Free Antivirus: http://forum.avast.com/index.php?topic=117113.0
2. Follow instructions: http://www.avast.com/uninstall-utility (Run this tool for all prior installed avast! versions..!!)
3. Reinstall avast! with the downloaded installer from point 1.
4. Reboot