I've set up a port forward PPTP (TCP 1723) to my server. From WAN I can connect ONE time only, on next attempt WinXP can't get user/passw validated (I recognize this from earlier router tests which didn't support the GRE protocol). After rebooting the PPTP server I can again connect ONE time. The server works just fine when I'm doing the connection LAN-LAN and with my old DI-524 there were no problemos from WAN.
Putting the server in DMZ doesn't help and AGL does not exist in my setup pages.
Any ideas, somebody?