'The Installation Failed' Mac Avast Free version

Every time that I try to download Avast (free version), it’ll complete the ‘Virus Definitions’ section but then pops up with a screen that reads ‘The Installation Failed
The Installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance.’
I’ve tried reinstalling the .dmg, restarting my computer and even formatting my hard drive.
Any help would be appreciated, thanks.

there shoul be some log files starting with “avast” in /tmp directory. Would you mind to share them with us?

Hello, thanks for the reply!
I’ve managed to get into my temp directory, which I found through Terminal, but I find no files or folders starting with ‘avast’. It’s mostly empty folders. Am I looking in the wrong place?

I’m another disappointed new, potential Mac user. In my case the installation failures have apparently been network problems (usually time-outs) while in the downloading virus definitions phase of the installer. It seems to start OK and then peter out. My wifi connection is on the slow side but it’s not THAT bad. I went looking for log files in the referenced /tmp directory. It’s a Yosemite system and the UNIX-type file system seems to live inside the root-level /sw, but there is no /sw/tmp., even though there are var and bin, etc. [to the other guy, it’s not the “temp” folder. It is (or should be) a root-(lowest)-level directory in the belly of the OS named tmp (no “e”), You get into that area (on my system anyway) by opening a finder window, going to the “Go” menu, selecting the “Computer” item and then clicking on Macintosh HD.]
Is there a way to download the current definitions directly elsewhere, say onto a different device and carry them on a USB stick?

Tried the installation again. This time (the 5th try?) it completed the virus definitions download phase (after about an hour!) and seemed to be proceeding with the installation Unfortunately it eventually crapped out again . In the installer window the last, “Summary” button on the left is highlighted in blue, but the larger information window on the right contains a graphic icon of a yellow triangle with a “!” character and the text, “The installation failed. The installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance.” There is also a line at the top "There were errors with the installation. You may want to try installin[cut off here due apparently to lack of space.] So how’s that for creative error handling! How about it Avast? Consider yourself contacted for assistance!

Hello, I will try to describe how the installation works, hopefully it will help a bit.

The first step of the installation is the download of our virus definitions from AKAMAI servers. If the download link is too slow, the connection will be dropped eventually. The conditions for the drop are not designed by us. We are using standard system ways of downloading online content. If the Virus definitions file download fails, no other log files are created as we have not yet started any installation of the product itself.

If the VPS is downloaded, the installation process is started and logs will start appearing in /tmp. Please note that /tmp is a temporary folder so when you reboot your mac it is deleted. Following files should be created depending on how far the installation went:

  • avastpostinstall-.log
  • avastinit-.log
  • avastuserinit--.log

These files hold the information about every single step the installation tries to do and how it went. Please send me those files to jakub.bednar at avast.com for investigation. I can’t provide any advice without knowing the root cause of the failure.