Temporarily disable DNS caching on Win Vista and Win 7
If you stop at step 3, it will disable DNS caching for the current session. The DNS cache will be re-enabled on the next system reboot or until you follow the instructions in step 4.
Please note that you need to be logged in as administrator. If you are not logged in as administrator, type:
cmd.exe in the search box found in the Start menu. Right click on the search result for cmd.exe and choose the option to "run as administrator." The terminal will appear and you can start from step 3 above.
Permanently disable DNS caching on Win Vista and Win 7