You either mean a 7250 or 7750 on verizon (click Options - About for the exact model number). The most common cause of this error is if your device is attached to a BlackBerry Enterprise Server and the policy is set to disable third party applications. That being said you mentionned that you are a home user. I would recommend that you wipe the device clean and re-install the latest OS onto it, this could resolve the problem. You can download the latest OS from: http://vzw.smithmicro.com/blackberry/
When running Application Loader, click Advanced and select to delete all applications and data, this will ensure that you have a clean device. I have seen a few times that a carrier will send you a device that had some bad settings on it, sometimes from a previous return.