I found that the problem I had was that Mass Storage Mode was enabled and my device was cabled so I could use BBSCREEN to capture images.
In that configuration, the MicroSD card was not accessible.
When I dis-connected the cable, I was able to upload from the MicroSD.
Also, when I turned off the Mass Storage Mode, I was able to upload from the MicroSD.
FYI in case anyone makes the same mistake as me in the future.