After updating Avast Internet Security to version 2015.10.0.2208 I am having problems with my wifi connection. I have Windows 7 Home Premium.
The connection to the wireless router is fine but the connection to Internet doesn’t work. The wifi icon indicates nearly full signal as usual but I can’t see any pages in any of the browsers I have.
I have an iPhone and an iPad that are connected to the Internet thru the same wifi and they work fine.
I noticed that Windows firewall was enabled, so I disabled it but this didn’t sort out the wifi problem. I think that this firewall may have been enabled after one of those automatic Windows security updates, because I know that I had it off before since I don’t want two firewalls (Windows’ and Avast’s firewalls) working at the same time. Then I found the option to disable Avast’s firewall in the UI but it doesn’t respond to this change; the Avast firewall continued to be enabled. I didn’t find any option to disable the whole antivirus thing for a while to confirm that Avast is the cause of the problem, as I think it is.
Then I restarted both the modem and the router and the connection to Internet in my Windows-based laptop was back, but only for a while.
I’ve had Avast for a few years and I haven’t had these problems before.
Windows firewall does not play the role but the service must be in running state. Make sure Windows Firewall Service is running.
(Computer>Manage>Services). Also check Internet Connection sharing and Remote Procedure Call are also running (These services are usually set to automatic so you can skip this step but just to make sure you should check them)
If Avast Firewall is disabled, there should not be a problem but if its active, please make sure ‘Internet Connection Sharing mode’ is ticked.
(Avast>Tools>Firewall>Settings)
Restart the PC and try and connect!
P.S You can disable avast altogether by right clicking on the tray icon>Avast Shield Control>Disable for the required time period.
I have enabled Windows firewall under Control panel > Windows firewall but I can’t find “Internet Connection sharing” and “Remote Procedure Call” in Windows. Is this in Control Panel > Internet > Connections ?
I have also checked “Internet connection sharing mode” in Avast.
(Settings > Tools > Firewall Customize > Preferences)
I had this problem and the GUI issue too. I had to uninstall AVAST 2015 and re-install it. So far so good…It’s worth a try Now GUI works aswell as no disconnections or wifi issues fingers crossed… 8)
I purchaded Avast 2015 & cannot turn on firewall or connect to internet. It keeps saying it is a public network. I have tried to change it but cant. Also the memory on the hard drive was at capacity and turned red with only 47G of memory left. I compressed and now have over half memory open…over 200G. Some really weird things going on making my computer virtually unuseable. I wont be able to get patches or anything without wifi connection!!HELP!!!
I solved this!!! I updated into AVAST Internet Security 2015. After that, when i am about to open my laptop and connect to wifi, i cannot anymore. What i did is, i opened AVAST tray… Settings > Update > (I forgot which tab i found it. :P) Then you will see a Notification that you need to Reboot your system! Click Reboot Now… And Laptp will restart! And alas!!! Wifi is now working! Probably, your pc wasnt Rebooted properly. (Although i knew i restarted it, by the windows restart? guess it doesnt work. It might really need to be restarted through AvAst.)
Good general rule to follow.
I have always rebooted my OS after software Updates/Upgrades whether I’m asked to or not.
A simple ‘reboot’ can often resolve apparent issues after updates.
Probably, your pc wasnt Rebooted properly. (Although i knew i restarted it, by the windows restart? 
guess it doesnt work. It might really need to be restarted through AvAst.)