If you have found that you are unhappy with your current OS and wish to go back to a previous version, follow these instructions and it will take you back.
First of all you need to make a back up of your device.
1. Uninstall your current OS from your PC. To do this you need to go to Start> Control Panel> Add/remove Programs> Highlight the device software you are using (you can check this by highlighting the device software and clicking on the "More Information" link) then click remove.
2. Download your preferred OS and install to your pc.
3. Go to C Program Files> Common Files> Research in Motion> Apploader> inside this folder is a file named Vendor.XML, delete this file. In this same folder is a program called Loader.EXE, double click to initialize the program.
4. Connect your device> Next> your pin will display Next> reading device> Next> Device App Version Check, this is where you want to check "Replace the device's applications with the older version provided by the BlackBerry Desktop Software">Next
5. On the Device Application Selection screen you can pick and choose what applications to include, the system will copy what you currently have on your device>Next
6. Device Back Up, ABSOLUTELY DO A BACK UP>Next
7. Complete the Application Loader Wizard> Next (this screen also serves as verification of the items you chose to put on your device, if you change your mind you can always hit the "Back" button.
Now during this process your device will reboot several times (you can watch the progress on the loader screen if you so choose) This is a completely normal process so don't panic. This process does take some time so DO NOT disconnect you device before it comes back on line.
Once back online verify that you have all your information back on the device. If for some reason it is not there, don't worry,
You made a back up before all this started (right). Just plug into your usb cable, launch the DM> back up and restore> restore and this will launch a window where you can choose the back up you created previously.> Next. Let it restore and you will have all the data back.
If you have an questions feel free to PM me or post on this thread.