Your DNS cache stores the locations (IP addresses) of webservers that contain pages which you have recently viewed. If the location of the web server changes before the entry in your DNS cache updates, you will be unable to access the site.
If you encounter a large number of HTML 404 error codes, you may need to clear your DNS cache. Once you clear your DNS cache, your computer will query nameservers for the new DNS information.How to clear your DNS cache
The following methods allow you to remove old and inaccurate DNS information that may result in 404 errors.
Windows® 8
- Press Win+X to open the WinX Menu.
- Right-click on Command Prompt and select Run as Administrator.
- Type the following command and press Enter:
ipconfig /flushdns
- If the command was successful, you will see the following message:
Windows IP configuration successfully flushed the DNS Resolver Cache.
Windows 7
- Click the Start button.
- Enter
cmd
in the Start menu search field. - Right-click on Command Prompt and select Run as Administrator.
- Type the following command and press Enter:
ipconfig /flushdns
- If the command was successful, you will see the following message:
Windows IP configuration successfully flushed the DNS Resolver Cache.
Windows XP, 2000, or Vista®
- Click the Start button.
- On the Start menu, click Run....Type the following command in the Run text box:
ipconfig /flushdns
- If you do not see the Run command in Vista, enter
run
in the Search bar.
- If you do not see the Run command in Vista, enter
MacOS® 10.7 and 10.8
- Click Applications.
- Click Utilities.
- Double-click the Terminal application.
- Type the following command:
sudo killall -HUP mDNSResponder
Warning: To run this command, you will need to know the computer's Admin account password.
MacOS 10.5 and 10.6
- Click Applications.
- Click Utilities.
- Double-click the Terminal application.
- Type the following command:
sudo dscacheutil -flushcache