Intermittent DNS Server error

I have been having intermittent DNS server issues ever since I installed AVG Antivirus Free on my HP laptop. I know it is not an issue with my home network, because no other device in my house (including my smartphone) have this issue. 

I have already tried most of the troubleshooting techniques recommended in this article (https://www.wikihow.com/Fix-DNS-Server-Not-Responding-Problem), including flushing my DNS cache and disabling extra connections. Though, I avoided some of the more advanced troubleshooting tips recommended by the article (like changing my DNS server address), for fear I might do them wrong and make things worse.

Strangely enough, this issue only occurs when I first turn on my computer. Every time I try to access any webpage on any browser, I get an error message about an issue resolving the DNS. My taskbar typically shows that I am securely connected to my home WiFi, but it still says "No Internet." This will happen for the first 10-30 minutes that I turn on my computer, and then suddenly I can access the Internet just fine... until the next time I turn on my laptop. But it's sporadic. Some days I won't have any issues (I managed to go for a month without any DNS issues), and then it will start up again. 

I installed AVG Antivirus Free in November 2021.  The DNS server issue began sometime in the middle of November. It happened a few times each week until mid February (mostly on days when I had accessed the Internet via hotspot on my smartphone, and when I came home I found that my laptop's DNS server wasn't responding). That was when I figured out how to flush my DNS cache, and that seemed to resolve the issue. I didn't have any problems again until mid-March. At this point, it's clear that clearing my DNS cache will not resolve the issue.

I am pretty sure my computer did an AVG update right around when the DNS issue began happening again. Could that have anything to do with it? This forum thread (https://support.avg.com/answers?id=9060N000000gD78QAE) seems to describe a very similar issue to mine -- both Jessica R and David Neill, who reported his tech issue later in the same thread. The only difference is that my issue is intermittent, while theirs seem to happen consistently anytime AVG is installed/enabled.

Probably the first step would be to verify if AVG Antivirus Free is indeed connected to the problem. Again, it isn't an issue with my home network, because all the other devices in my house are fine. And it's not an issue with my default browser, because I also tried it in another browser and it had the same issue. It doesn't appear to be anything to do with my DNS cache, because I have already tried clearing my DNS cache.

Can you tell me how to temporarily disable my AVG so I can find out if that fixes the problem? (Once you explain how to disable AVG, I won't be able to actually try this troubleshooting technique until the issue pops up again.) Alternatively, I could try uninstalling and reinstalling AVG Antivirus Free. Where can I find the most up-to-date version for me to reinstall?

It seems like that solved the issue. I used my Hulu app via hotspot on Monday (and another web-based app via hotspot Tuesday), and I had no issues with my laptop when I got home.

Actually, I uninstalled AVG Antivirus Free using the second method from the FAQ, by going to my Control Panel and uninstalling it that way. Will that make any difference?

So it looks like that's all I need. Thanks for all your help!

Though, if the same issue ever comes up again, I assume I can just reply to this same thread, right?

Thanks for giving such a quick reply!

To answer your questions:
-My OS is Windows 10. 
-I have AVG version 22.2.3223 (build 22.2.7013.717).  
-The most recent virus definition is 220403-4.
-The UI version is 1.0.653
-I am pretty sure I don't use a VPN. That's essentially a special private connection to the internet that's different from a WiFi connection, right? When I got to Control Panel > Network and Internet >  Network Connections, it classifies the internet connection I am using as simply "WiFi." And I definitely don't have the AVG Secure VPN service. Does that answer your question?

Yes, it definitely seems like connecting through hotspot is what seems to trigger the issue. Do you think that's the cause of the issue, even though I never access the Internet via hotspot on my laptop, just on my phone? It seems strange that something I do on my phone would somehow affect my laptop's Internet connection even though my phone is fine. How does that work, exactly? Is it because I am logging into the same Gmail account using two different devices, each with their own different DNS settings, and that's confusing AVG?

I changed my DNS settings per your instructions, after I uninstalled and reinstalled AVG Anti-Virus Free. Also, it's worth noting that this time I installed AVG's  free phone app that apparently came with the desktop version I had just downloaded. When I first installed AVG last time, I didn't download the app for my phone. Now that I have it on my phone, too, would that factor change any of your troubleshooting suggestions? Do I need to edit the DNS settings on my mobile phone, too?

I won't be able to share a screenshot just yet, because the issue hasn't appeared since I last posted on the forum. Rest assured, if it happens again, I will take screenshots. With any luck, though, it won't, because I followed your instructions for changing my DNS settings. One way to test this is if I try the thing that almost consistently seemed to trigger the DNS issue: logging into a web-based app via hotspot. I'll try logging into my Hulu app via hotspot when I'm at work tomorrow, and then see if that triggers the issue when I get home.

Most of the time, it seems to happen whenever I connect to the Internet via hotspot while I am on break at work. I log into Netflix, Hulu, or another web-based app at work. Then, when I get home and turn on my laptop, I get the DNS error message. There are exceptions: I think once in the past week I edited something on Google Drive on my phone while at home (and presumably on my home WiFi), and then afterwards I got the DNS error message on my laptop, but it was only for less than 5 mins, and it seemed to disappear after I flushed my DNS, so maybe that's a fluke? But almost every time this happens is right after I stream a movie via hotspot. Funnily enough, it doesn't seem to happen whenever I open an app via hotspot that I had previously opened on my home WiFi. E.g. I would download a movie from Disney+ at home, leave the window open on my phone as I take it to work, and then watch it on my break. I did that for a month and experienced no DNS issues whatsoever. I assumed the problem was solved. Then, on March 25th, I decided to log into Hulu while at work, rather than watching a movie I had downloaded while on my home WiFi. Boom! It started all over again.

Do all of these things just point to your theory that configuring my proxy server should fix it?

For now, I am going to take advantage of my Internet while it's working, since I need it for a stay-at-home job. But tomorrow afternoon I will log into Hulu on hotspot to test to see if the issue seems to be fixed.

It seems like that solved the issue. I used my Hulu app via hotspot on Monday (and another web-based app via hotspot Tuesday), and I had no issues with my laptop when I got home.

Actually, I uninstalled AVG Antivirus Free using the second method from the FAQ, by going to my Control Panel and uninstalling it that way. Will that make any difference?

So it looks like that's all I need. Thanks for all your help!

Though, if the same issue ever comes up again, I assume I can just reply to this same thread, right?

Thank you for writing back to us, Giancarlo.

Firstly, we'd like to inform you that you don't need to change the proxy settings in your mobile.
Secondly, now that you've reinstalled your AVG Antivirus Free using our Clear tool, we request you to keep monitoring the siatuation & if the issue resurfaces again, please get back to us immediately.
We'll offer you appropriate assistance to further investigate this issue & if we're unable to resolve your issue, we'll collect the necessary AVG logs from your computer, escalate your case to our higher level of support.
Thank you for understanding in advance!

Thanks for giving such a quick reply!

To answer your questions:
-My OS is Windows 10. 
-I have AVG version 22.2.3223 (build 22.2.7013.717).  
-The most recent virus definition is 220403-4.
-The UI version is 1.0.653
-I am pretty sure I don't use a VPN. That's essentially a special private connection to the internet that's different from a WiFi connection, right? When I got to Control Panel > Network and Internet >  Network Connections, it classifies the internet connection I am using as simply "WiFi." And I definitely don't have the AVG Secure VPN service. Does that answer your question?

Yes, it definitely seems like connecting through hotspot is what seems to trigger the issue. Do you think that's the cause of the issue, even though I never access the Internet via hotspot on my laptop, just on my phone? It seems strange that something I do on my phone would somehow affect my laptop's Internet connection even though my phone is fine. How does that work, exactly? Is it because I am logging into the same Gmail account using two different devices, each with their own different DNS settings, and that's confusing AVG?

I changed my DNS settings per your instructions, after I uninstalled and reinstalled AVG Anti-Virus Free. Also, it's worth noting that this time I installed AVG's  free phone app that apparently came with the desktop version I had just downloaded. When I first installed AVG last time, I didn't download the app for my phone. Now that I have it on my phone, too, would that factor change any of your troubleshooting suggestions? Do I need to edit the DNS settings on my mobile phone, too?

I won't be able to share a screenshot just yet, because the issue hasn't appeared since I last posted on the forum. Rest assured, if it happens again, I will take screenshots. With any luck, though, it won't, because I followed your instructions for changing my DNS settings. One way to test this is if I try the thing that almost consistently seemed to trigger the DNS issue: logging into a web-based app via hotspot. I'll try logging into my Hulu app via hotspot when I'm at work tomorrow, and then see if that triggers the issue when I get home.

Most of the time, it seems to happen whenever I connect to the Internet via hotspot while I am on break at work. I log into Netflix, Hulu, or another web-based app at work. Then, when I get home and turn on my laptop, I get the DNS error message. There are exceptions: I think once in the past week I edited something on Google Drive on my phone while at home (and presumably on my home WiFi), and then afterwards I got the DNS error message on my laptop, but it was only for less than 5 mins, and it seemed to disappear after I flushed my DNS, so maybe that's a fluke? But almost every time this happens is right after I stream a movie via hotspot. Funnily enough, it doesn't seem to happen whenever I open an app via hotspot that I had previously opened on my home WiFi. E.g. I would download a movie from Disney+ at home, leave the window open on my phone as I take it to work, and then watch it on my break. I did that for a month and experienced no DNS issues whatsoever. I assumed the problem was solved. Then, on March 25th, I decided to log into Hulu while at work, rather than watching a movie I had downloaded while on my home WiFi. Boom! It started all over again.

Do all of these things just point to your theory that configuring my proxy server should fix it?

For now, I am going to take advantage of my Internet while it's working, since I need it for a stay-at-home job. But tomorrow afternoon I will log into Hulu on hotspot to test to see if the issue seems to be fixed.