If you enter a website in your address bar, like PCMag.com, your computer does not know where to go. Instead, the address is searched for on a Domain Name System (DNS) server that matches an IP address that your computer should visit.
It's as if your friend says, "Meet me at Tom's Bistro" – if you do not know where Tom's Bistro is, you can look up the address in the phone book and go there.
However, it may take a long time to scan the phonebook before finding the right address. To speed up this process, your computer will save some of these entries for later access. To continue with the previous metaphor, it's like writing "Tom's Bistro ̵
The site you visit may have changed servers and is no longer under the cached address, or you may have malware trying to redirect frequently used pages to malicious sites. (If you suspect that the problem could be malware you may want to perform a scan of with one of these tools .) Whatever the case may be "rinse" "Your DNS cache must start over, so your computer will again look for web addresses on the DNS server.
This process is different from deleting the web cache in a web browser, of course, if clearing your browser's cache If you have not solved the problem, deleting the DNS cache may be the next step, so do it on Windows and macOS from the command line. (If you are using Linux, you will need to look for instructions for your particular distribution.)
Clear the DNS Cache on Windows
If It's You On a Windows computer – on any Windows computer that even goes back to XP or older – e requires deleting the DNS just a simple command. Click on the start menu and enter "cmd". Right-click on the command line and select "Run as administrator". In the Command Prompt window that appears, enter the following command:
ipconfig / flushdns
If successful, the command prompt reads "The DNS resolver cache was successfully emptied." Please visit the website again and see if the problem has been resolved. If this is not the case, the Web site may be down, you may have Wi-Fi problems, or you may have a more serious network issue on your page that needs to be investigated. If this is another user's computer, you can always try troubleshooting remotely.
Empty the DNS Cache on a Mac
Mac users need to run a quick terminal command to clear the DNS cache, but the command depends on their MacOS Version off. First, press Command + Space to open Spotlight and search for "Terminal." Press Enter to open it.
Most modern versions of macOS – from OS X Lion to macOS Sierra – use the following command. Type it into the terminal and press Enter:
sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder
If you are using OS X 10.10.1, 10.10.2, or 10.10.3, you must do this Run this command instead:
sudo discoveryutil udnsflushcaches; sudo discoveryutil
You do not see a success message for both commands, but you can check the problem site and see if the issue has been resolved. If not, you will need to go through the other troubleshooting steps.