Accessing XP Pro via Terminal Services from Windows Mobile

The end result of this procedure should allow you to click on the Terminal Services in Windows Mobile’s Programs section, enter your virtual domain you can create using DynDNS, and DynDNS will direct the Remote Desktop/Terminal Service traffic to your home cable/DSL modem’s external IP address which then gets port forwarded to your target desktop PC.

What you’ll need:

1. Windows Mobile 5 or similar device
2. DynDNS account (free) http://www.dyndns.com and associated domain (also free)
3. Remote Desktop configured on your XP Pro system
4. Properly configured software Firewall and/or Firewall Router connected to broadband modem

DynDNS

The purpose of dynamic DNS is that if the IP address to your router or modem is dynamic, the DynDNS allows you to create a virtual domain that you can map to your IP address, and you can download a client

1. On your network computer, from the main page, click AccountàCreate Account. You’ll be prompted for a login username (to log into DynDNS.com to modify your account as needed), email address, password.
2. After accepting the terms, you can choose and create your virtual domain, something maybe like “bigfoobar.ath.cx” and you’ll have the option of assigning your external IP address to that domain. In other words, if your external IP is 123.123.xxx.xxx and you assign bigfoobar.ath.cx to that IP address, if you now ping bigfoobar.ath.cx, it will return your external IP address.
3. Now, since you have a dynamic IP address, you’ll occasionally need to update the database as your external IP address changes. A free client from DynDNS can be found at https://www.dyndns.com/support/clients/ . Some of the things this client can do for you are (quoting the DynDNS site itself):

· Allows detection of IP locally or by a remote server

· Runs as a system service

· User-defined IP detection interval

· Performs forced updates once a month to prevent Dynamic DNS hosts from expiring due to inactivity

· Allows scheduling of Offline setting for maintenance

· Supports e-mail notifications

· Logs to screen and to file with a visual warning when update error occurs

· Supports multiple interface devices or LAN connections

· Customizable icons for visual notifications of client status

So, properly done it can run in a “set it and forget it” fashion.

Remote Desktop

To enable Remote Desktop Connections:

1. Right-click on My Computer, click Remote
2. Click Allow users to connect remotely to this computer
3. Click Select Remote Users, and you should see your current Windows login account name under the white region, something like “JoeDonBaker already has access.” If need be, you may add additional users (if any).

If you like, you can alter the default Remote Desktop Protocol (RDP) port of 3389 to another port number. Rather than edit the registry yourself, you can use a free utility for both your mobile Device and Windows system:

1. On the Pocket PC’s side I recommend Alexander Groß’s RDP Port Switcher, and you can download it from http://www.it99.org/axl/download/rdpportswitcher-1.0-setup.zip

Most RDP clients on desktop systems simply allow you to enter the IP address followed by the port you’d like to use, such as 192.168.0.2:3395. However, since the Windows Mobile Terminal Services doesn’t allow this, you must either edit the registry manually or use the tool above. Simply copy the CAB to your device and install it. It will put RDP Port Switcher in your Programs Group, and by running the app it will change the default port that the Windows Mobile Terminal Services client uses to connect to the XP system.

2. On the PC (server) side, if you wish to change your RDP port, I suggest trying the free version of Remote Desktop Port Change from http://www.intelliadmin.com. Download and run the EXE, and from your PC select “Local System” and enter the port number you’d like to use. Obviously, the mobile device’s port you set above and the XP system’s remote desktop port must match.

Router/Firewall

If you have a firewall router between your broadband modem and your system, you’ll need to do a couple things. Depending on the software in the router, you’ll need to do the following:

1. Log into your router, and open up port 3389 or whatever port number you chose if you decided to change it in steps 1 and 2 above. Depending on the manufacturer you should be able to specify “Port Forwarding”, create a TCP or TCP/UDP service type, and use the port number, say 3389 as the start and as the ending port, and then specify the internal IP address. IMPORTANT: You will likely need to have your target PC’s IP address set to STATIC, so that the port forwarding always forwards to the correct system.
2. If your PC has a firewall installed, open up the appropriate port in your firewall software to permit RDP connections.

Finishing Up

All that needs to be done now is to test the procedure. If you have a wireless router on your home network you should be able to test from inside your network to see if everything works as expected.

1. Turn on the Axim’s WLAN.
2. Start up the Terminal services.
3. Enter your DynDNS domain name in the “Server:” field of Terminal Services.

With any luck, you’ll see a popup saying “Connecting to: <your DynDNS domain>” followed by a screen similar to this (I cheated and used my server for this screencap), but the XP screen would be similar. Ordinarily you’d see various window controls in the command bar, but I think I clicked overzealously on something in the menu bar. But you get the general idea. This is in landscape mode.

Simply log in as you would if you were in front of the system, and you're done!.