Overview

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Operating systems cache or store away IP addresses for future use. It does so to speed up the connection time as fetching data from the DNS (domain name server) every time you connect to the network requires a lot more time and resources than necessary.

However, when the IP addresses do change, the operating system will still try to pull the IP address from its stash rather than from the DNS. Flush DNS command removes this stored cache and forces your device to retrieve the information from the DNS again. The Winsock reset restarts the communication required between your device and the network. 

Critical Concepts

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• Please refer to KB0033280 for a full troubleshooting guide

Steps to Take

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Windows

1. On the taskbar search, type "Command Prompt."
2. Right click on Command Prompt and press "run as administrator."
3. When asked whether to allow Command Prompt to make changes to your computer, select Yes.
4. Open Command Prompt
   
5. Type the command ipconfig /flushdns then press enter
   
   
   
   
6. Type the command ipconfig /registerdns then press enter
   
   
   
   
7. Type the command ipconfig /release then press enter
   
   
   
   
8. Type the command ipconfig /renew then press enter
   
   
   
   
9. Type the command netsh winsock reset then press enter
   
   
   
   
10. Restart the computer

Mac

1. Close all browser windows.
2. Open Terminal. You can do this by pressing the Command key + Space Bar at the same time to open your Spotlight Search. Or click the magnifying glass in the top right hand corner. Then type "terminal." Click on Terminal. 
   
   
   
   
3. In the Terminal window, type the corresponding command for your Mac OS X version:
   
   
   • OS X 10.11-10.15 (El Capitan, Sierra, High Sierra, Mojave, Catalina): sudo killall -HUP mDNSResponder
     
     
     
     
   • OS X 10.10 (Yosemite): sudo discoveryutil mdnsflushcache
     
     
     
     
   • OS X 10.7 - 10.9 (Mavericks, Mountain Lion, and Lion): sudo killall -HUP mDNSResponder
     
     
     
     
   • OS X 10.6 and older: sudo dscacheutil -flushcache
     
     
     
     
4. Press Enter, then enter your password to finish clearing the DNS cache.