T-Mobile SDA Smartphone FAQ

Frequently Asked Questions for the T-Mobile SDA with Windows Smartphone 2005 Newbie

What does “Application Locked” mean?
What does “Locked” mean?
How can I unlock my phone?
How can I unlock my “Application Locked” phone?
How much memory memory do I need?
Is the Compact Framework 2.0 part of the platform?
Can my SDA phone connect to my company’s Exchange server?

What does “Application Locked” mean?
When researching ways to unlock your phone, or when trying to deploy a Smartphone 2005 application to your phone, you will likely come across this term. It means that the SDA’s security policies by default lock it down so that applications cannot be deployed. This is even true for signed assemblies.
Security policies are stored in the device’s registry. Your device likely did not ship with a registry editor, so you will have to find one and deploy it to your device before you can make changes to the registry.
I have a Thawte certificate, and Thawte is a trusted root authority (which means that their root cert is pre-installed on the SDA). I should have been able to deploy a signed application, but for some reason the signing did not work. Maybe I will try to revisit this a some later point in time. I am all set for now, because I removed the ->application lock.

What does “Locked” mean?
A locked phone is network-locked, which means you can only operate it with a SIM card from the provider that you received the phone from. When you get your SDA, it will only work with T-Mobile SIM cards. If you insert a Cingular SIM card and boot up the phone, it will display a message similiar to “This phone is network-locked. Please enter lock code:”, and will prompt you for the code. Without the code, you will not be able to use the phone. If you have a good story, such as heavy international travel, you may be successful in getting the unlock code out of T-Mobile support. Because the SDA is so easy to unlock, I don’t think it is worth-while trying.

How can I unlock my phone?
This process is documented in detail by the folks from SPV-Developers. The process requires that you application-unlock your phone and then run an executable on your computer while the phone is connected through ActiveSync. The exectuable can be downloaded for free from spv-developers.com and worked without issues for me. Once your phone is unlocked, you can use any SIM card from any provider. Even the unlocked SDA does not want to connect to non-T-Mobile networks, though, which could be helpful considering the not so great T-Mobile coverate.

How can I unlock my “Application Locked” phone?
Most sources describe the process as a combination of making changes to the registry (will enable deployment of signed code), plus running a utility on the PC that uses the Remote API (RAPI) to entirely unlock the phone (will enable the deployment of unsigned code).
See Windows Mobile 5.0 Application Security for details.

How much memory do I need?
More. Seriously, get a 2GB Mini SD card before you attempt to deploy an application to the phone. It seems that the SDA comes without the .Net CF 2.0 (Compact Framwork). The first time I started a deployment from Visual Studio, it prompted me that it needed to deploy CF 2.0 as well. Subsequently, the first Hello World application deployment ran out of memory on the phone. I am still waiting for my 2GB card to arrive before I can report success there. Tips for freeing up memory, and wealth of other information, can be found here.

Is the Compact Framework 2.0 part of the platform?
No, the SDA ships with CF 1.0 only. There is usually not enough memory to install the CF2.0 redistributable, which means that you have to extract the .cab from from package. manually copy it to the memory card on the device and run it from there.

Can my SDA phone connect to my company’s Exchange server?
The short answer is: yes! The long answer is longer. If the Exchange server is freely accessible from the Web, you can access it directly. Most corporate networks shield their Exchange servers from the Web, though.
If your company uses a Microsoft VPN, either PPTP or IPSec, you can configure your SDA to tunnel the Exchange traffic throught the VPN. Bust what if your company uses a 3rd party VPN? This was my situation (my company uses both Citrix and Cisco). I could not find a freely available VPN client from either vendor. But when I configured ActiveSync to use the URL of our Outlook Web Interface instead of the Exchange server name, synchronization worked, and it worked from outside the corporate network without a VPN connection. I am not sure how the phone connects to Exchange, but I assume that Active Sync uses a WebServices layer that the Outlook web application exposes.