View Full Version : Dial Up Networking Error

10-07-2002, 09:57 PM
When logging onto the internet I get the following:

"Dial Up Networking was unable to complete the Connection"
Error 720
Dial Up networking could not negotiate a compatible set of network protocols you specified in the server type settings. Check your network configuration in the control panel then try the connection again.
So I go and open up Network in control panel, click on TCP/IP, then properties, then click OK and OK and I can log on and off without problem until I reboot the PC. Then the problem is back. Its as if its losing the binding from TCP/IP to the dialer.

So far I have:

Removed and reloaded Client for Microsoft Networks, Dial up Adapter, TCP/IP.
Removed and reloaded Communications in Windows setup (Add remove programs)
Removed and set up the dialer
Reloaded windows (98SE)
Reloaded the modem drivers
Tried specifying the ISP IP addresses in both the dialer and Network setups.
Checked and double checked the recommended settings in Networks and dialer settings

Help! It has to be something I can not see because its so obvious.

Sam H
10-07-2002, 10:09 PM
Sounds like you have made an error with the network protocols when you were setting up your internet connection.
Go to the control panel and double click network connections, right-click you internet connection and go to properties, now go to the networking tab and with internet protocol (tcp/Ip) highlighted click properties. If this has use the following IP address and use the following DNS server addresses selected then un-select these and select the other option of the obtain IP address automatically and choose DNS server addresses automatically.

Hope this helps.


Terry Porritt
10-07-2002, 10:57 PM
Also check this: go to Network, highlight Dial-Up Adapter, click properties, click bindings, and make sure the TCP/IP box is ticked, OK your way out and re-boot.
Of course, if that box is already ticked the problem is elsewhere, still its something to check on.

flamingo rinse
11-07-2002, 03:02 PM
Hi there - also, you might need to set the password element to allow unencrypted text......I don't think that's the default setting and usually I've had to go unencrypted for passwords...some where in modem or DUN settings but can't remember precisely where,sorry.

Graham L
11-07-2002, 04:43 PM
In the Connection properties, there is an option for openinhg a window before connection. Tick that, and it will tell you what it is doing as it happens. That's much more helpful than giving an error message when it gives up.

12-07-2002, 03:19 PM
Tried that thx Sam, no go.

12-07-2002, 03:20 PM
Checked that Terry, all OK.

12-07-2002, 03:21 PM
The session fails right after I enter the password.

Terry Porritt
12-07-2002, 04:32 PM
Hmm.. you havent said which OS you are using, if Win 95 then its a good idea to update to the latest version of DUN, 1.3 or 1.4 I think, and to winsock2.
This site also mentions the 720 error when 128 bit encryption isnt installed on your system together with other general stuff and MS links about the 720 error.


14-07-2002, 05:23 PM
Terry, great site, but still no go. I can only access the internet if I first go to TCP IP properties under 'Network' then click OK Ok and then dial in. (I don't change any of the settings) I'm using Win 98SE, and I'm thinking about doing an Fdisk followed by a clean windows install. It seems the binding to TCP/IP does not survive a cold boot. Maybe something to do with the registry? I don't have the skills to go there.