Can not mount USB device

[doug]

The system is FreeBSD 10.3-RELEASE-p7 #0. All commands are execured as root.

file -s /dev/da0s1
/dev/da0s1: DOS/MBR boot sector, code offset 0x58+2, OEM-ID "MSDOS5.0", 
sectors/cluster 8, reserved sectors 38, Media descriptor 0xf8, sectors/track 63, 
heads 16, hidden sectors 8192, sectors 831488 (volumes > 32 MB) , FAT (32 bit), 
sectors/FAT 813, serial number 0x482393a9, unlabeled

I ended up with the following attempts

mount -t msdosfs -o -m=644 /dev/da0s1 /mnt/
5mount_msdosfs: /dev/da0s1: Permission denied

dmesg:
(da0:umass-sim0:0:0:0): Error 13, Unretryable error
g_vfs_done():da0s1[WRITE(offset=19456, length=4096)]error = 13
(da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 00 00 20 26 00 00 08 00
(da0:umass-sim0:0:0:0): CAM status: SCSI Status Error
(da0:umass-sim0:0:0:0): SCSI status: Check Condition
(da0:umass-sim0:0:0:0): SCSI sense: DATA PROTECT asc:27,0 (Write protected)

mount -t msdosfs -o -m=644,-M=644 /dev/da0s1 /mnt/
mount_msdosfs: /dev/da0s1: Permission denied

dmesg:
(da0:umass-sim0:0:0:0): Error 13, Unretryable error
g_vfs_done():da0s1[WRITE(offset=19456, length=4096)]error = 13

All other variations got the same error (Permission denied)

The USB stick is readable in windows 10. I thought it was a data disk it turns 
out to have 2 install program files one for windows and one for mac.