In Winbox go to: system -> stores -> disks. You should see there the name of your usb drive, i.e: usb1
Select it and click “Format Drive”. Obviously all data on this drive will be deleted.
Then go to files. There should be your usb mounted in root folder under the name: /usb1
Now, click: IP -> SMB -> Shares -> Add, and type the name of the share you want to create and the path where usb drive is mounted: /usb1
In ‘SMB Settings’ window check ‘Allow Guests’ and verify that everything works fine. Later you can uncheck this option and add allowed users..
Abubaker Siddiq Lasania
Virtual IT Support