I installed a Kingston Data Traveler (which is approved by Inter-Tel) backups. It worked fine twice. Now I get a "Voice Processor: Drive not ready." error. I tried a different USB drive. The backup never gave me an Operation Complete message. Although it appeared that all of the messages were saved on the drive.

With happened with our Axxess system. We had to reset the voicemail. But that was using an external VPU.