If a previous version of Blackberry Desktop Manager is installed on the computer (4.7 or earlier), it is advised to uninstall it and ensure that all the RIM Virtual Serial Ports are uninstalled before installing Blackberry Desktop Manager 5.0.1. To uninstall Blackberry Desktop Manager:

1. From Control Panel, open Add/Remove Programs
2. Select “Blackberry Desktop Software x.x” and click on “Change/Remove”.
3. Click Next
4. Select “Remove”, click Next
5. Click Next
6. Click “Remove”

Next Steps after successful download:

1) Click on Save.
2) Close the BlackBerry Desktop Manager software.
3) Double click on downloaded executable file.
4) Click RUN on dialogue box.
5) Choose Setup Language from the dialog box
6) Install Shield will install all required modules on PC/laptop.
7) Allow the BlackBerry Desktop Manager software to restart at the end of the installation.

System Requirements can be found here.