Hi,

Normally we would see this problem on a machine running Catalina, so for the benefit of others who find this post I will mention the solution:

Apple menu - System Preferences - Security and Privacy - Privacy tab. On the left, select 'Files and folders'.
Look for 'Band-in-a-Box' in the list of apps and make sure 'Removable Volumes' is checked.

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Since you have High Sierra, I don't think that will apply. If you select the Band-in-a-Box folder on the USB drive and go to File - Get Info, what does it say in the Permissions section?


Andrew
PG Music Inc.