Re: DUN could not negotiate compatible protocols

Joe Brewer (joe@admin.net1.net)
Fri, 29 Aug 1997 15:15:07 -0500

>I just noticed something intersting re: Windoze 95 DUN. I have had several
>customers experiencing the "could not negotiate compatible protocols"
[...]
>With 95, if the customer dials in with the "terminal window after dialing"
>option turned on, logs in with their ID, password and sends the PPP option
>from the menu, then tells windows to continue, we have nearly a 100%
>success rate (I saw 1 failed attempt out of the 50 or so that I personally
>tried and I think it was a modem compression hiccup) with connections. The
>same customers, using the regular 95 authentication, seem to have less than
>50% success rate, getting the "couldn't negotiate protocols" error a very
>high percentage of the time.

Windows 95 is stupid. Disable IPX/SPX and NetBEUI in your dialer properties
and in the bindings section of your dial-up adapter (under control panels,
network). The "Internet Setup Wizard" almost never gets it right. And while
you are in there you may want to turn off support for WINS, assuming you are
an ISP and don't use it. Once this has been done the error should go away and
they will authenticate faster as well.

If you only disable the above unused protocols in the dialer properties and
not in the dial-up adapter, we have seen random results. It seems that some
times Win95 uses the information from one, some times from the other. We just
take it out of both and it works well. There may be other solutions, but this
works for us.

Joe "Unix bigot" Brewer
joe@net1.net