This may solve the above error message in the following situation:
- Client is using web browser to connect to server over http (typically using port 5800)
- VNC server is running behind a NAT router
- Client is on WAN side of router, server is on LAN side
NB: The error message is not displayed when a client using IE7 connects to server version 1.0.2 - only a blank screen results!
Symptoms:
- After typing in the URL (using either the WAN IP address that is port forwarded to the VNC server or a hostname/domain name that resolves to this address), the Java application loads
- After choosing the Run option in the "Warning - Security" dialog, the error message "Network error: could not connect to server xx:5900" is displayed, where xx is the IP address or hostname the user entered in the URL
Solution:
This situation can arise if the port forwarding is correctly set up on the router for VNC-http (typically port 5800) but not for the standard VNC service (typically port 5900). Although the user specified port 5800 in the browser address bar, the error message is being reported for port 5900 - i.e. the user has successfully connected to the http server running on port 5800 as part of the VNC server application, but the Java app cannot then connect to the "real" VNC server running on port 5900. It's obvious really. And probably in the documentation too...
Versions...
I have tested this with server versions 1.00 and 1.0.2, and with Firefox 1.5.0.9 and IE7 browsers. Note that with the combination of IE7 and server 1.0.2 the actual error message is not displayed - just a blank screen, which is not very helpful
I hope this is helpful ... this problem had me scratching my head for a while. And then again when I thought I'd fixed it but actually hadn't! (Hence the edit.)
And apologies for any inaccuracies - I'm not a tech guru so my use of technical terms may be rather approximate.