Are you referring to the Verizon Wireless Backup Assistant Plus pages that appear when you connect your RAZR to your computer with the USB cable?...
If installation from the RAZR failed, you can download the latest version of MotoCast from mymotocast.com
Which USB mode are you in? Have you tried Media Device (MTP) mode instead of Mass Storage mode?
Which part of MotoCast are you trying to use?:
- MotoCast Wireless to access content on your PC from your DROID 4?
- MotoCast USB to sync...
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