After finally sorting the 6GB of log files problem I had the other day I updated Windows to 8.1. After it completed and I logged in Avast disappeared, nothing in Add/Remove, Program Files, ProgramData or Registry, ran Avastclear in safemode to check if there was anything left and there wasn’t.
Is Avast fully compatible with 8.1 or should I install a different AV solution?
Thanks in advance 
Yes it is compatible, were you using the latest avast version, avast! 2014 (9.0.2006) ?
See http://forum.avast.com/index.php?topic=136785.0 for more information and download links. ].
I don’t know what the windows 8.1 update entails, if it is a destructive update or if it would remove installed AVs and enable Defender or not.
I have just completed the 8.1 update and all Avast would say about it on completion was that my flash player was outdated (and it was ) Otherwise no problems experienced
I am about to do the update from Win8 Pro to Win8.1 via the Windows Store.
I will report any issues/problems after I get it all done, however I really don’t expect an issue.
We’ll see
We’re on Avast 8 Business Protection (8.0.1490). We just updated a few machines to Windows 8.1 Pro (through the Store upgrade process) that was released today. However, after the entire process is finished, Avast is gone. It’s completely removed from the system.
I’ve posted over in that forum as well, but it appears it’s happening here too. I can’t upgrade us to 9 as we’re on the business suite and it’s still on 8.
If you install Avast 8.0.1490 on Windows 8.1, it will say it’s not compatible. Even though it looks like it’s working and the shields are up - it will blue screen the machine.
I was using the latest Avast before I did the Windows 8.1 Pro update and it completely wiped out Avast. Not installed and not on my drive after 8.1 was done. So I re-downloaded Avast to re-install it.
But now I wondering what is going on as the new download from today, only has 3 shields listed on the left column during a custom install. The previous had 8.
Here are the Sheilds that Avast had with Windows 8:
File
Web
Mail
p2p
im
network
script
behavior
Now with the Avast installer downloaded today to install in Windows 8.1, I only see these Shields listed:
File
Web
Mail
So it appears to be missing 5 of the 8 previous shields. I really don’t like that it is missing the Network and Script shields. But I really wish it wasn’t missing any of the Shields. So I haven’t re-installed Avast yet. Trying to learn what is going on.
From the FAQ : http://www.avast.com/faq.php
The number of real-time shields in avast! 2014 is reduced by merging some of them to another. The P2P Shield, IM Shield and Behavior Shield are now a part of the File System Shield, while the Network Shield with Script Shield are a part of the Web Shield.
Awesome. Thanks for the confirmation that the protection is still there. I will go ahead and re-install Avast on my 8.1 system. While they are merged, it would still be nice to see them listed out during the install. Maybe list them as Sub-heading that can’t be altered.
If you had 8 shields then you didn’t have the latest version of Avast when you upgraded to Win 8.1 From earlier posts in this thread, it’s been stated that there was no problem when running the ‘latest version’ of Avast.
For what it’s worth, Avast has disappeared off my computer now too after installing Windows 8.1. I got here from a web search about the problem
You don’t mention what version of Avast you were running when you upgraded to Win 8.1
Is it really relevant what version was being used?
Avast should have envisaged the release of 8.1 and produced a product which runs with it.
I simply asked as it as been stated by Essexboy and others that with latest version of Avast there were no issues.
I am presently in the process of Upgrading as well and for me that was information I was interested in knowing!
This happened to me, on both my desktop and my laptop. Avast is just not there. I can’t find it - it’s not there to uninstall, I can’t find it by searching icons.
It’s as if I never installed the bloody thing. I suppose I can always just get a new copy and reinstall and put my key in there, but it’s slightly concerning that an upgrade to 8.1 “wiped out” Avast.
I was using Win8 Pro 64bit on desktop and Win8 Pro 32bit on laptop. The desktop was using Internet Security 8.0.1497 Laptop was using whatever the current free version was, not sure there.
UPDATE: It also appears to no longer be INSTALLED, I couldn’t find it on my hard drive anywhere. Currently downloading a new version, but that’s somewhat offensive that they would uninstall that, which is what appears to have happened.
Ok, I downloaded Avast again and re-installed it. It’s working fine now. Internet Security
I still had to reboot my computer to get all the shields running properly
It was so strange because it was like it was never on my computer, completely removed, all traces that I could see
Which version were you using before you installed Win 8.1?
Was it v8 or v9 of Avast?
Internet Security
… Version? As in were you using 8.0.1497 or the latest v9.0.2006 build?
Internet security (AIS) has different avast versions 7.x, 8.0 and 9.0 (a.k.a avast Internet Security 2014), so the information being asked for relates to the version number AIS, 8 or 9.
The reason this is important, is if it was the older version 8.0, then it may not have been compatible with windows 8.1 and may have been removed.