Guys,
some of you are reporting some v5 related problems when upgrading from v4.8.
This is not such a wonder, given that we're currently doing over 400,000 such upgrades a day (so even if it worked in 99.9% cases, for example, it would still fail for 400 people a day).
Now, we'd really to know what's going on on these problematic machines.
To start with the analysis, it would be very useful if you could send us the setup log which contains all the information about the update.
The file is usually located in the
C:\Program Files\Alwil Software\Avast5\Setup
folder, and is called setup.log. You can either attach it here, or (even better, or if you're concerned about privacy) send it to my email address (click the envelope icon below my picture).
Thanks much for your help,
Vlk