Purge the cache

 Undex a Dos (cmd.exe) prompt, enter:

 ipconfig /flushdns ipconfig /registerdns 

Disable the DNS cache

1. Start Registry Editor (Regedit.exe).

2. Locate the MaxCacheEntryTtlLimit value under the following registry key:

HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesDnscacheParameters

3. On the Edit menu, click Modify. Type 1, and then click OK.

4. Quit Registry Editor. 

disable "negative DNS caching"

Modify the registry with :

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters] "NegativeCacheTime"=dword:00000000

"NetFailureCacheTime"=dword:00000000

"NegativeSOACacheTime"=dword:00000000