Step by step OS install (Layman's edition)
This is about as simple and as step by step as I can put it. Experts, let me know if you think I'm wrong.
Step by step on how to install OS
BEFRE ANYTHING, BACKUP YOUR PHONE JUST IN CASE ANYTHING GOES WRONG!!!
Remove your memory card.
1. Remove all installed Operating Systems from add/remove programs and OS folders from C:\Program Files\Common Files\Research In Motion\Shared\Loader Files ( if you have any installed)
2.Download (if you haven't already) and install OS onto your computer.
3. Remove RIM internal tools from add/remove programs in control panel ( if the OS that you're installing comes with them)
4. *Optional! If you don't want to shrink anything out or prefer not to use Shrink OS, skip this step*
Download Shrink-A-OS, unzip, and place all of those files into your OS folder which will be here: C:\Program Files\Common Files\Research In Motion\Shared\Loader Files. Now, right click on Shrink-A-OS inside that folder and click Run As Administrator. At the top of Shrink-A-OS check the box that says "Shrink-A-OS is inside my Current OS Folder." Remove what you want and the click "Shrink My OS!" Close it out.
5. *Skip this step if you used Shrink-A-OS, as it has already been deleted.*
Navigate to C:\Program Files\Common Files\Research In Motion\AppLoader and delete the vendor.xml file
6.In the same folder C:\Program Files\Common Files\Research In Motion\AppLoader double click the Loader or if you're having trouble you may have to right click and choose run as administrator (its the one with the pic of a phone) file, click next and it will show your pin click next again. It will go through a couple of steps and then a box will pop up with what is going to be installed. You can also remove or install things here. (If you want to be sure you are installing the right OS you can check here: The top line is Blackberry Software xxx. Select this, then click details at the bottom. A box will pop, click the Modules tab. There are 2 columns. The left column is what is already on the phone, example 4.7.0.148 and it will have a bunch of this number and the right column shows you what is going to be installed on the phone, example 4.7.0.151 and again you will see a bunch of this number in that column. So now you know what is going on the phone) As long as everything is there that you want installed click next and then another box will pop up and tells you what is going to be installed and what is going to be deleted. Click Finish and let it do it's thing and install. (This can take a LONG time in some cases, do not unplug until it is finished.
7. Enjoy your new OS!!