I am having the same issue on windows 10...
So this started happening about a month ago and I finally got to the point in troubleshooting I could pinpoint where the issue is.
Randomly it seems, local internal network DNS entries were getting modified to completely random IP addresses. For example, I would have a web server at 10.40.x.x and all of a sudden I get 404 errors, and when I ping, the IP would be 10.21.x.x or a different subnet within our network. After examining my domain controllers and DNS, I found they are translating the IP correctly, but the bad one is coming from a loopback IP of 127.42.x.x.
So in troubleshooting, I decided to turn off Malwarebytes web protection, which appears to be running a local proxy server and doing some DNS filtering. As soon as I turn it off, I don't even have to flush the DNS cache, the pings return the correct IP from the domain controllers/DNS servers.
Is there a setting somewhere, where I can tell it NOT to override IP addresses for local domains? I don't want to turn this off every time I come to the office just so I can continue to browse to internal resources without issue.
EDIT: I am using 3.0.6 on Windows 10 Pro Creators, Production Ring.
Here is an example:
Webprotection is off:
Pinging server.domain.com [10.40.x.x] with 32 bytes of data:
Reply from 10.40.x.x: bytes=32 time=3ms TTL=124
Webprotection turned right back on:
Pinging server.domain.com [127.42.0.0] with 32 bytes of data:
Reply from 10.40.x.x: bytes=32 time=3ms TTL=124
30 min after webprotection turned on:
Pinging server.domain.com [127.42.0.1] with 32 bytes of data:
Reply from 10.21.x.x bytes=32 time=1ms TTL=127
It's doing something completely wonky with the DNS with a local DNS proxy associated with WebProtection. I have my entire domains excluded, but that doesn't seem to help.