How can I stop a Windows 95 machine acting as a browse master or backup browser?

On the Windows 95 machine start the Network Control panel applet (Right click on Network Neighborhood and select properties)

Click the Configuration tab

Check the list of installed network components for "File and Printer sharing for Microsoft Networks". If this is here goto step 5.

If this is not installed click the Add button, select Service and click Add. Select Microsoft and select "File and Printer Sharing for Microsoft Networks" and click OK. Click OK to the configuration tab and when asked reboot the machine.

Select "File and Printer Sharing for Microsoft Networks" and click Properties.

In the property box click Browse Master and select Disabled in the Value box.

Click OK