Updating your hosts file in Vista 64-bit

I came across an interesting issue this morning whereby my hosts file had simply vanished.  For the unitiated amongst you, this file presents a kind of local DNS for Windows TCP/IP which essentially means you can make up a domain and point it at an IP address and have that apply to your machine only.

Now, normally this file is located in systemroot\system32\drivers\etc where systemroot is C:\Windows.  However, on 64-bit, System32 is replaced by SysWOW64.  Not such a big issue, except when you go looking for your hosts file from inside a 32-bit application such as Flex Builder / Eclipse.

For some reason, in Vista 64-bit, 32-bit applications can’t see the 64-bit tree, meaning that the hosts file is essentially invisible.  So, how the hell do we get round this?

Well, backdoor ahoy – there is a solution.  In your C:\Windows folder (%systemroot%) create a “sysnative” folder and browse through that.  Bingo! your good old 32-bit folder structure should now be present, and low and behold your hosts file.

Posted by Neil Middleton on 03 Nov 2008