Before I get into story mode, this in theory will work for ANY model HTC Desire, but for reassurance for people with or looking to buy the A8183 version that operates on WCDMA 850mhz (e.g. Telecom XT), this will also definitely work for you. I found conflicting reports when I was searching, but as I said, this process worked for me, it should also work for you.

So, I’ve been a foundation XT customer, and despite some “teething issues” – On a whole I’ve received better coverage and speeds on XT than I did before I ported from Vodafone. What I haven’t been happy with, is the phones. Even though they’ve finally moved to WCDMA, the frequency they are using is less common, therefore phone manufacturers tend to be playing catch up.

I had nearly purchased an iPhone 3GS, and then I heard rumours of the Telstra Next G network getting a version of the HTC Desire. The good thing about this is the Next G network runs on the exact same frequencies as Telecom’s XT, so in theory, any phone that works on Next G would work on XT.

Fast forward nearly 9 months; Telstra did indeed get an 850mhz version of the HTC Desire, and they are in fact unlocked and will work out of the box with a Telecom XT sim card. That of course leaves you with all of the Telstra/Big Pond customisations (Which are HORRIBLE), and Eclair rather than the latest and greatest Froyo. After nearly biting the bullet and getting an iPhone4, I got pissed off with how they were being sold in NZ and ended up ordering a A8183 Desire, and a few days later it arrived.

I had it in my hand for about two hours and with the help of a mate and some Googling, have rooted the phone and am running vanilla Froyo. By following the below, you can have the same.

Step 1 – Purchase a Desire

As I said above, in theory, this will work on any Desire. Myself and a few mates have purchased off www.mobicity.co.nz, and have had pretty good luck. The only downside is some of the time their stock levels are incorrect. Mine didn’t ship from Aussie for 4 days even though they said it was in stock and ready to go. They made up for it by shipping it priority and including a car charger.

Telecom XT Version: http://www.mobicity.co.nz/htc-desire-nextg.html
Other NZ Networks: http://www.mobicity.co.nz/htc-desire.html

Step 2 – Root your Desire

This is simple as. There are multiple methods for this, however I chose the Linux LiveCD way of doing things due to running Win7 64bit, which apparently can cause some problems. Either way, you need to root your Desire. If you have another way of doing it, all good, this is what I used, and it worked amazingly easily.

I followed the instructions found here: http://myhtcdesire.com/modding/how-to-root-your-desire-easily-method-1 – Which I’ve changed slightly and stuck below

What You’ll Need

1. Your new Desire.
2. Slax Linux Live CD

The Guide

This guide is written assuming that the computer you’re using to do this is connected to the internet via an Ethernet cable. If you’re connecting over Wireless, Slax may not be able to connect to the internet. That’s ok, just do step 5 in your normal OS, and copy the file to a USB key or your phones storage, ready to be copied onto your Slax desktop.

1. Burn your Linux LiveCD to a blank CD using your burning software.
2. Keep the CD in the CD drive and restart your computer.
3. You should see Slax starting to load up – if not you may have to change your boot sequence so that the CD boots before your hard drive.
4. You’ll see a Slax start screen – select “Slax Graphic Mode (KDE)” then wait for Slax to load up.
5. Once you get to the Slax desktop, open Firefox using the icon in the taskbar at the bottom, and go to: http://unrevoked.com/recovery/. Click “Download for Linux” and save to your desktop.
6. Extract the file you download.
7. On your Desire go on Settings > Applications > Development and make sure “USB Debugging” is turned on.
8. Connect your phone to your USB cable.
9. Run Unrevoked (file’s called reflash) and wait a couple of minutes whilst it roots your phone. It’ll tell you what is going on, and your phone will be doing stuff.
10. When it returns the success message you know you’ve successfully rooted your phone! This also installs the Clockwork Recovery mod, which allows us to flash the phone.

Yes, really, it is that simple to root your Desire.

Step 3 – Flash your Desire

This again is pretty easy.

1. Download Stock ROM with Radio from here (link to originating forum thread).
2. Copy that file to your phones flash card and rename it to “update.zip”
3. Turn off your Desire, and turn it on holding down the Volume Down button, which will boot you into the Clockwork Recovery screen, which looks like this:
4. From there, you want to select “wipe data/factory reset”
5. After that has completed, select “apply sdcard:update.zip”
6. All going well, your Desire will reboot into its new vanilla HTC ROM

That, in theory, is all you need to do.

Now you have a pre-rooted HTC Desire, running Vanilla HTC Froyo.