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I ran into an issue with my DNS cache in Windows 8.1 (and Windows 8 before the update).
I have a little webserver running and I purchased a domain for it.
After I changed the DNS settings of the domain to point to my virtual server, I opened my cmd and typed "ipconfig /flushdns" like I did several times before to get the new IP.
I noticed that this time it did not work. The old IP was 5.XX.XX.XX and the new one is 37.XX.XX.XX. I decided to try it again later (changed the DNS records yesterday) so I tried it again some minutes ago. But everytime and regardless how often I clear whatever cache it always show the old 5.XX.XX.XX IP -.-
I spammed the command mentioned above several times, I cleared Chrome's cache (read somewhere in the web, not sure if it really helps), I smashed my head against the walls but no result.
I tried to ping the domain with my laptop and it works.
I pinged it using online tracerouting tools and it always shows the new IP.

Is there any other way I might have missed to completely clear my DNS cache?

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It is not your cache that is the problem, it is an inherent part of the way DNS works. Your machine is getting its DNS resolution from somewhere else, and the caching is taking place there. See this:

hum.is.                 13485   IN      A       182.160.128.100

That is a DNS record from my DNS server. The second column is the TTL and is the number of seconds remaining before my DNS server will refresh the record for hum.is. It does not matter how many times I flush my local DNS, every time I ask my DNS server to resolve hum.is, it will give me the same answer.

It won't go back to the authoritative name servers for hum.is and see if there is a new IP address until that time expires - in about 3.7 hours.

You can set the TTL value on your A records for your domain. Sometimes the default can be very high - I have seen them set for several days. Ideally you set this to a low value - say 60 seconds, several hours (a length of time greater than the current ttl value) before making a change, then put the TTL back to a higher value (to avoid unnecessary taxing of the DNS system) after the change.

This is what people are referring to when they talk about "DNS propagation", only it isn't propagation at all, it is just cache values timing out.

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