H2testw is a simple and useful freeware tool to check for any errors in your USB drive. It is an easy to use program designed to enable you to test USB sticks for various kinds of errors. It can also be used for any other storage media like memory cards, internal and external hard drives and even network volumes. You need to select the drive for checking error and start the scan.
The function of H2testw is quite simple: It fills the chosen target directory with test data and then reads it back and verifies it. H2testw does not overwrite or erase any existing data. It doesn’t do any low-level tricks so administrator privileges are not required. If your hardware is working properly H2testw will not harm any existing data.
There is also an endless verify option which continuously starts checking for errors. The tool can find out corrupted sectors and sectors which have been altered. Once the tests are complete, you need to manually remove the files added to your drive or USB.