Yahoo search fails

Upon hearing about the new Yahoo search engine I thought I'd try it.  Main 
Yahoo page comes up but when I search the result is invariably : 'Server not 
found'.

I have two separate machines (a Dell 2.5Gh running RedHat 9, and an old Dell 
laptop ditto).  Same occurs with both, using either Opera 7 or Mozilla 1.2.1.

However, on an old Windows98 machine the search works, using either IE 5 or 
Opera 7.

Not sure if anyone can help on this one.

Many thanks
Robin