If all you did was click on "back up", then only your data was backed up (calendar, address book, etc). Applications are not backed up. You'll have to re-download everything.
Originally Posted by Swaggerr
If you want to backup your 3rd party apps for next time, do the following:
1) Start up Desktop Manager and connect your blackberry.
2) Click on "Device Switch Wizard"
3) Click on "Start" for "Switch Blackberry Devices"
4) De-select everything in the 3rd column except "third-party applications" (it should be the only one checked).
5) Click next and wait for it to do it's thing.
6) When it's done, a window will pop up asking you to connect the new device. Don't touch anything!
7) Do a search on your computer for files/folders that contain your PIN in its title. (It's usually in your temp directory, such as C:/temp.)
8) Copy the folder to a safe place. This is your back up.
9) Go back to desktop manager and cancel the device switch.
To restore the 3rd party apps, go to "Application Loader", and then "add/remove applications". Click on "Browse" after DM has scanned your phone. Browse your way to the folder you had stored in step #8 above. Load the alx file. A list of all your 3rd party apps will pop up. Check them to install them.
The "back up" feature doesn't back up your device, it just backs up your data since that's the only important and irreplaceable thing in your phone. Your apps can always be re-downloaded.