Windows 95 issues DNS lookups for its own NetBIOS name resolution every five minutes or so. This is a particular problem for LAN ISDN users, as the requests are directed at PSINet’s nameservers and hence bring up the telephone line or ISDN line unnecessarily.

The option in question is known as ‘DNS for Windows’ resolution. Windows 95 defaults with this option enabled, NT and 3.11 do not.

We suggest you apply the change to Windows 95 machines in the first instance and check that the problem has stopped.

This does not affect regular DNS lookups from your TCP/IP applications such as Netscape and Telnet, nor does it affect Windows’ workgroup networking on your LAN. It merely tells Windows to use DNS only for TCP/IP lookups.

Windows NT 4.00

Run Control Panel, and choose ‘Network’
Select the ‘Protocols’ tab
Click on ‘TCP/IP Protocol’ and click on ‘Properties’
Select the ‘WINS Address’ tab
Ensure that ‘Enable DNS for Windows Resolution’ is NOT ticked.

Windows NT 3.51

Run Control Panel and choose ‘Network’
Select ‘TCP/IP Protocol’ from the menu list, and click on ‘Configure’
Click on ‘Advanced’
Ensure that ‘DNS for Windows Resolution’ is NOT ticked.

Windows 95

There is no option in Win 95 network choices to disable DNS for Windows resolution. However, it can be done via a registry change.

Download the file fix95dns.exe. Run this program - it will make the necessary change to the registry for you.

NB. You need to have set up the DNS options in Control Panel BEFORE applying this patch, as Windows will grey the options out because it treats the DNS as disabled.

Please note that PSINet take no responsibility for this programme. This is used entirely at your own risk. Additionally, it must be noted that if any network changes are made eg. changing IP addresses or subnet masks, the machine must be re-booted and the patch programme must be re-run. This is not an ideal fix for this problem, but it is currently the best solution recommended by Microsoft.

Windows 3.11 (Using Microsoft TCP/IP)

Run ‘Network Setup’ from the ‘Network’ group in Program Manager
Click on the ‘Drivers’ button
Select ‘Microsoft TCP/IP-32’ from the list
Click on ‘Setup’
Click on ‘Advanced’
Ensure that ‘Enable DNS for Windows name resolution’ is NOT ticked.