PChelpware Network Anomaly.

[bnichlsn]

I have been using UltraVNC SC successfully for several years to offer Remote Assistance to my customers. As Uvnc does not work with Vista, I am now testing PChelpware. I have come across what I am calling a network anomaly. Let me detail my setup:

My home network basically consists of 2 PCs (1 desktop, 1 laptop) connected to an unmanaged switch which in turn is connected to a Netgear DG834 ADSL router. A wireless access point is also wired to the switch.

The desktop, running Windows XP, on fixed address 192.168.0.5 is hardwired (ethernet) to the switch.

The laptop is dual boot, running XP and Vista and has a wired connection to the switch or a wireless connection to the WAP (not both connections at the same time!). With the wireless connection, the laptop address is fixed at 192.168.0.2 (XP or Vista). With the wired connection the laptop address is 192.168.0.25 (XP or Vista). This is not a fixed address, but it did not change during the tests.

The router has port 5500 configured to forward to addresses 192.168.0.2 (laptop) and 192.168.0.5 (desktop). Both addresses are enabled, but with PChelpware, any combination of address enabled/disabled makes no difference. (Correct port forwarding is vital for Uvnc to work!). PChelpware appears to use Upnp to do the port forwarding.

I have PChelpware_viewer installed on both PCs. I have the same test server installed on both PCs. Thus, I can use either PC as the viewer and the other as the server.

The tests I have done are as follows:

1) With a local IP address configured into the server exe file, the system works perfectly. Either PC can be the controller. Any laptop combination of XP/Vista/wired/wireless works.

2) With an internet address of 80.xxx.xxx.xxx (my WAN address) configured into the server exe file, the system works perfectly with the desktop as the controller. Any laptop combination of XP/Vista/wired/wireless works.

3) Here comes the crunch!
With the laptop as the controller there are 2 problems. The internet address of 80.xxx.xxx.xxx (my WAN address) is configured into the desktop server exe file. The system only works with (laptop Vista and wireless) or (laptop XP and wired)! The combinations (Vista/wired) or (xP/wireless) do not work!

When the desktop server fails to connect, the error message I get is:

"Failed to connect.
A connection attempt failed because the connected party di.......
Init network failed".
(The error window is too small and does not permit all the message to be viewed!).


Can anyone suggest what the problem is and/or how to fix it?


It looks like a router problem as the local connection works.

Is it a Upnp problem? Before every test, I ensure that Upnp mapping is OK, unmapping and remapping if necessary.

Notes.
a) I am using a Direct Connection.
b) I have tried the new XP and Vista drivers. No difference.
c) I have replaced the 1SCDLL.DLL and 1SVCDLL.DLL files with the newer versions. No difference.


I look forward to your comments.

[bnichlsn]

I have solved the problem myself! Upnp was indeed the problem. The solution is not to use it! Just use normal Port Forwarding as per UltraVNC.

In the PChelpware_viewer.exe window, do NOT tick the Auto Map box. It was not necessary to disable Upnp in my Netgear Router.

By enabling the correct Port Forwarding rule in the Router, I can now use my laptop as the Viewer with the laptop configured as XP/Vista/Wireless or Wired in any combination. The desktop PC worked OK anyway.

So there you have it! Easy!!! (when you know how!).