In this post,MiniToolwill tell you how to fix the proxy server ain’t answering error.
So why does this glitch notice appear?
A proxy server can be used to anonymously access certain web pages or other web connection services.

And then you should run a full system scan to verify if there is any remaining possible malware infection.
Step 2: SetView by: Large iconsand then clickPrograms and Features.
Step 3: Click any recently-installed applications, then clickUninstall.

Then chooseUpdate & Security.
Step 3: In the pop-up window, chooseScan optionsto continue.
Step 4: ChooseFull scanand then clickScan nowto perform the full system scan.

Step 2: Typeinetcpl.cplin the box and clickOKto openInternet Properties.
Step 3: Go to theConnectionstab, and then clickLAN settingsat the bottom of the window.
If it is, uncheck the box, and then clickOKto save changes.

Step 5: Reboot your machine to look to see if the error appears again.
Here is a quick guide:
Step 1: OpenInternet Propertiesand then go to theAdvancedtab.
Step 2: A new window pops out, check the box next to theDelete personal settingsoption.
ClickResetand wait for the process to complete.
Step 3: Reboot your machine and then peek if the error is fixed.
Related post:How to Fix ERR_PROXY_CONNECTION_FAILED?
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