If you don't delete the other vendor's file, the software won't be able to install the software on your carrier-locked device.You can visit Crackberry.com's OS4.5 Beta forum for discussion and help should you run into issues.Beta operating systems are not officially released for good reason: They're often full of bugs and could potentially void your warranty or worse, render your Black Berry unusable.(Read, "How to Reload the Operating System on a Nuked Black Berry," if you ever find yourself with a bricked 'Berry.
To check which version of Desktop Manager you currently have, you should launch the program via Windows Start menu Desktop Manager.
If you do decide to install unofficial software and it's from a carrier that isn't your own, you should be sure to ditch the software's vendor XML file before beginning installation.
To do so, open your PC's Program Files App Loader and then delete the Vendor file, which is in XML format.
Then click the Help tab on the main screen and choose About Black Berry Desktop Manager.
The software version will be listed on the General tab.