Symptom
USB is not getting recognized after reload in WS-C3850-24P-LWS-C3850-24S-L.
Large file transfers from external USB to internal flash may fail with I/O errors.
Conditions
USB drive formatted as vFAT (FAT32) inserted in front panel USB port.
Workaround
Remote file copy such as FTP or TFTP will work.
Issue is not currently seen on IOS XE versions 3.6.x or 3.7.x.
Reinserting USB drive after reload may help.
Formatting USB drive as EXT2 (Linux file system) may help with large file transfers.
Further Problem Description
This is not a hardware failure.
Issue is not reproducible with all USB drives.
