VPN authentication issue

We have a small network of about 70 systems (small, private school). Our server is running Windows Server 2003. As far as I know it is up to date on all of its updates.

I am attempting to establish a VPN to the network. Using the wizards I have set up RRAS and it all works just fine as long as I am using XP as the client. My Vista systems (running 32bit, either Home Premium or Business/Enterprise) will not authenticate. They hit the server and then fail to verify the user name / password.

Has anyone encountered a similar problem and do you have any suggestions?

Thanks

Well you could try stroing the password. go to Control panel and click users for there on your right hand side select manger network passwords and and the username and password over there and then try..

If that doesnt work u need to tell me what is the VPN server and what is running on it. and also check whether port 1723 is open on you router.


Regards

Thanks very much for the prompt reply.

Let me expand on the original post --

Yes, I have 1723 and the GRE protocol 47 open --

We are running windows server 2003 R2 Standard Edition, Service Pack 2. I am not attempting anything fancy. I set up RRAS and then used the wizard to create a VPN connection using PPTP.

We have Cox Cable connected to a D-Link router. The router settings to allow VPN, as well as specifically allow PPTP are all enabled. I can VPN into the account using an XP system, but when I connect using Vista it returns an error message stating "The user xx.org\yyy has connected and failed to authenticate on port VPN4-250. The line has been disconnected."

The user name is correctly matched to the Windows AD login and as I said works ok on an XP system but not on a Vista system.

Your suggestion of storing the network password produced the same results. I found threads about SP1 for Vista breaking vpns. As such I uninstalled both SP1 and uninstalled my Windows Live One Care since the same threads suggested One Care did not correctly open the ports. I verified the Windows firewall was configured correcly, but still received the same error message.

The only other oddity that I know of is that I am running Windows Home server as a backup system. I double checked the router at the home end (another d-link) and verified that Port 1723 and the VPN settings were enabled.

Any other suggestions would be greatly appreciated.