There are tests available for the exclusive purpose of scanning removable drives.
Here is the information on the test taken directly from the Advanced User Guide:
Removable Drive Tests
This module tests removable storage drives.
Linear Read Test
This test scans for surface defects on the test media, reading entire tracks beginning with the center track and moving outward to the maximum track. If any errors occur when reading a track, the test logs an error.
Pattern Test
This test determines if the drive is successfully recording data to media. The test writes test patterns to the test media, then reads the data to verify it is correct. If the read data does not match the written data, the test logs as Failed.
Note: If power fails during this test, the original data from the drive may be lost or corrupted.
In addition, if you wish to perform HDD testing on one drive you can designate which drive you would like to test within the Diagnostics and Tools tab in Windows or after pressing "R" to Run Service Center in DOS.
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