This customer had previously asked me to setup remote desktop, so that a software vendor could connect and update its software remotely.

I had previously setup the port forwarding (d-link call it: virtual server) to allow port 3389 to pass through to the main PC.

Also had to disable the windows firewall (asked to do so by the software vendor), in order to allow access. I’ve since found the correct way to bypass the windows firewall without disabling it!

A week later, I’m told that remote desktop access is no longer working… Grrr

I take a look, and I see that the main PC now has a different IP address… So I connect to the DSL-G604T router and then setup for a fixed IP address. I also setup the PC with a fixed IP address (not using DHCP)… it takes a while, but eventually, everything is working correctly.

I try remote desktop from a second PC (to the internal LAN IP address) and it works well.

I try using the same PC to connect to the “external” fixed IP address… but no go.

I try many different variations, but still no go.

By looking at some online help, I see some mention of the need for a firmware upgrade. I’d like to avoid this if I can, so I keep searching. I also find a vague mention that you cannot use remote desktop to control a “remote” PC, if that PC is on the same LAN(ie I cannot “go out to the internet” and then “connect back in”).

So I call my wife and ask her to try connecting from the office PC… But it doesn’t seem to work. She eventually realises that I didn’t say to put a dot between the first and second IP numbers (Doh!)… but even after that has been corrected, it still doesn’t work.

At this point, I’ve been onsite for 4.5 hours, and I’m running out of ideas. I decide to try ultraVNC, but don’t have time to test it… I promise to return, once I have a solution.

Once back at the office, before trying VNC, I take a look at RD, … I hit the options button, and I notice the domain is set to “martindom”… I clear the domain field, hit the connect button, and I’m surprised to see that I’m connected.

I quickly call the customer (and apologise for disrupting their PC while they are working) and tell him that the PC is finally able to be updated.

I login a few days later and disable VNC, and I email the customer, strongly advising that he updates his passwords, as they can easily be guessed.

Looks like RD cannot be properly tested without using a remote site…