OK…thx…then I have no idea why when I installed V10 FREE on only one of my PCs that all of the other PCs in the house could no longer get onto the internet thru my Dlink router. Once I uninstalled V10 from that PC all the other PCs (they have combo of V8 & V9 on them) could then get out to the internet.
Wow, this is really scary and I must say unbelivable. Do you have to have the V10-PC running in order for the others to be blocked from the net?
I did not try too much experimentation…the machine is HP DM4 2Ghz so very fast…and I use Avast & MBAM Pro…very clean.
I have DLink DIR655 Router…four other PCs and even have Guest in house with MAC Pro notebook.
So, I did a CLEAN uninstall on V8…installed V10 FREE (Custom, Shields Only)…came up OK at login and seemed a LITTLE slow…not a lot. I could immediately login to the internet and even tried my router…was OK. Then after about few minutes the PC started to slow to almost unresponsive. I tried to do CTRL-ALT-DEL for tasks manager to see what was taking the resources and it delayed so long that Windows said some message about this could not be launched, etc…trying to get even Windows Explorer to come up was 15+ minutes. I clicked on Avast 10 and console took 10 minutes to come up. During all that time my guest on the MAC said she could not get on internet and I also tried other PCs…all of which would not work. The router activity LEDs were banging away with something going on. So, I was not able to really do a reboot thru Windows so HARD reset and into safe mode where I uninstalled V10. I then did a clean uninstall and now unless I can find the V9 offline installer will have to go back to V8 since I still have it. Once the machine came back from reboot after uninstall all other PCs & MAC could now see internet.
In the future I would recommend attempting to ping your router to see if you can get a response.
press the windows key + R, type CMD.exe, Then type ipconfig /all, You should see your default gateway ip address, note this down for future use. Then type Ping followed by your gateway's ip address.
You should see that theres packets commuicating between the router, if not then something certainly has gone wrong. You can also ping the gateway from the mac using the network utility application (use the spotlight search to locate the program.) click ping and then input the default gateway, It will ping the same as your windows ping would.
I would have pinged but could not even get command prompt to come up…the system was SO slow.
As FYI, I do know my router & gateway IP address.
Seems a lot of other posts on V10 about WebShield & HTTPS scanning.
Could my issue have been that Avast 10 was out there scanning on this single PC so much links that it killed bandwidth at the router which blocked other PCs getting online ? Also maybe this also killed my memory & CPU on the PC ? I’m just reading various posts and connecting the dots…but perhaps not accurate.
Other datapoint is that I have SugarSync installed on this PC which at reboot checks to make sure all my files are synced with web. I was able to EXIT out of this hoping that its closing would have helped the performance and/or web issue but it did not.
WebShield (with or without HTTPS Scanning) does not generate any traffic on its own, so it has not the capability to kill your bandwidth. Currently I have hard times imagine how this (and also anything else in current avast) could ever affect your (or anyone else’s) other computers. If in doubt there is nothing easier that plug the computer of the ethernet socket for a while and see if the problem goes away.
I have been experiencing intermittent issues which I believe are related to secure dns.
Windows 8 machine. Name resolution would randomly stop working.
The following were symptoms:
- Upon running command “ipconfig /release && ipconfig /renew” problem went away for about 30 seconds. After that renewing an IP address made no difference (i.e. problem persisted).
- nslookup would not attach to listed dns server. I was using google server 8.8.8.8 for testing purposes. I could ping the address, however simultaneously could not perform nslookups.
- I have a router between my client and my firewall. I ran a packet sniff on the port for all traffic destined to 8.8.8.8. I could see my pings going through, however did not see my nslookup requests.
- I turned off secure dns under active protection in avast, still did not fix my problem.
- I turned off the avast firewall service under services.msc (I’m not sure, but I still don’t think this fixed it)
- utilizing “netstat -on” I found numberous connections associated with a PID I later looked up via windows taskmanager. This PID was associated with an avast service. Upon ending this task I believe I was finally able to gain name resolution.
Thus, I believe my name resolution problems were directly related to avast, and likely related to securedns.
Just an update.
After restarting avast firewall service “services.msc” I still had an error message in AVAST. Something about Avast Background Services failed to start… I am surmising this is why simply turning off “Secure DNS” did not immediately solve my problem.
Anyway, I have since stoped the “Secure DNS” feature in Active Protection.
I am hoping that a reboot of the computer with “Secure DNS” turned off will solve my problem long term. It’s hard to know however since the problem is intermittent… Has happened two other times in the past few days.
Yet another update…
It happened again. I have still not rebooted the machine, so still a good test machine…
This time I went directly to services and stopped all 3 avast services. (Antivirus, Firewall, Vbox). Upon restarting all 3 services problem immediately went away. (In fact the web page I was trying to access came up instantly without having to re-request).
I may have still been correct on my initial assumption that a reboot (or service restart) is still required for the disabling of “Secure DNS” to take effect.
If it happens again I will try to determine which of the 3 service restarts fixed the issue.
This Avast Secure DNS setting is not a good thing to have if you have any type of parental controls on your network…
example, I use OpenDNS, and if “secure DNS” is enabled, it bypasses all filtration from OpenDNS and my network is free as a bird and anyone with this “secured DNS” feature enabled on their computers can go to any website they wish…
How can a piece of software like a Avast circumvent the DNS settings I have a t the router level? - I have even enabled “Intercept port 53” on my router which prevents users from using their own dns server…yet, Avast can bypass it like it was nothing.
Not very good Avast… not very good at all.
Hello,
I have the same problem. After restarting the PC following an update, I was cut out of the internet (Ethernet connexion). Troubleshooting (Window 7 32 bit) said “the DNS server cannot be reached”. Funny, another PC (Wifi connexion) connected to the same router showed no problem. After turning off Web shield protection, the problem was gone.
Well, what could I have done wrong, I asked to myself? Oh yes, Avast update AND Windows update, but only one reboot. How stupid of me. OK, uninstalled completely Avast, run Crap Cleaner and Glary Utilities, got rid of broken registry entries, clean install of Avast… and the problem is there again! I am not with Web Shield protection turned off: if I turn it on I lose the DNS.
Hi guys. I just had new installs of Avast Free 2015 kill two customer’s internet connectivity. The one from last night was a real emergency situation and the only thing I could come up with was to eliminate the IE icons and just use Chrome (which worked where IE quit). (Brand new Asus laptop Win8.1)
The second situation (today) I uninstalled using Revo… but the Win7 connectivity tray icon still said “No Internet Connection”. I could ping locally 127.0.0.1 and 192.168.1.1 (router) but nothing outside AFTER the uninstall. (Win7HmPrem Gateway dsktp abt 1 year old).
So? Forced to use my smart phone to beg for help through Google - and found a barely understandable Pakistani guy’s YouTube video where he simply loaded OpenDNS’s DNS settings - immediately fixed the problem. For some stupid reason Avast (even after complete uninstall) has overridden the native DNS settings… and NOTHING you do will fix that - short of using Google’s 8.8.8.8 and 8.8.4.4 or OpenDNS’s 222 and 220, etc., etc.
So Avast? WTF. Fix this total train wreck mess or loose whatever’s left of your customer base. I, for one, do NOT have time to dick around with small crap like this when I’m at a customers HOUSE cleaning viruses for a small living - for crying out loud.
Sure - I’ll give this thing a second chance - but only after I read here (and elsewhere) that this problem has been overcome. Good lord what a hassle.
Bill Trail
PC Doctor
Macon, Georgia July 3, 2015
PS: SO MUCH FOR YOUR BIG WOOP CONSUMER GUIDE MAGAZINE 1ST PLACE. Kiss THAT magazine goodbye too.
How did you remove the pr-installed trial of the third party AV that comes on an Asus computer ???
Not removing it properly before installing Avast or any other resident AV can result in all sorts of problems.
See my signature for help in successfully installing Avast.
The latest update is horrible if you have a LAN and need to access computers locally. Avast has added a plug-in to verify DNS requests and changes the IPs without any warning. So you end up with an external IP instead of the internal IP which causes programs to fail of course, your only option is to use the IP and not the name. There is no way to disable this behavior, at least not in the free version, without disabling Avast totally. I used wireshark to find out that some Avast DNS server was accessed and modified the IP.
This new feature might be useful to detect/prevent “Man-in-the-middle” attacks or such, but it should at least be in the settings with some options to disable it or add exceptions.
Until this is fixed I have to disable Avast or rollback to a previous version.
Since my post in May I have uninstalled Avast, upgraded to Win10, tried Panda, removed it because it would not let me finishing install another software, cleaned registries, removed remnant files with Glary Utilities, Crap Cleaner and Revo Uninstaller, removed Windows.old… Today I have reinstalled Avast, hopin no memory effect, but the Web Shield problem is still there! The only way to get a connection to the internet is to turn off the web shield.
I even tried to add the Web Shield to the list of authorized programs in Windows Firewall, thinking that might be the culprit, but I do not find any executable corresponding to the Web shield, just a dll.
I’m now staying with Web shield turned off, but it’s quite surprising that such an issue affecting so many users (do a web search and you’ll see how many!) has not been addressed yet.