H2testw was developed 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.
The executable file H2testw.exe needs no installation and can be
directly run. It was developed for Windows XP and Vista. It should
also work under Windows 2000 but was only tested on XP and Vista.
Windows 9x/ME is not supported. You can use the older command line
program H2test under these operating systems.
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.
BUT: _If_ the hardware is defective then H2testw is designed to find
that defect and might as a side effect damage existing files.
Therefore: IF YOU SUSPECT A USB STICK OR OTHER STORAGE MEDIA TO BE
DEFECTIVE, EMPTY IT AND TEST IT COMPLETELY WITH H2TESTW. Only empty
media can be fully tested with H2testw. In order to be able to
reproduce the results we recommend to format the media (quick format
will do) and then test it.
H2testw writes files of up to 1 GByte to the chosen destination and
names them 1.h2w, 2.h2w, 3.h2w and so on. If the target directory
alread contains such a set of files H2testw will offer to verify them.
If there are any other files named *.h2w it will refuse to work. In
that case please erase all files *.h2w and hit the Refresh button.
After it is done the software leaves its test files on the medium.
You can erase them if you like or verify them again — if it’s a USB
stick for instance with another PC.
The check box “endless verify” does just that: It puts the verify
routine in an endless loop that stops only if an error is found. This
is meant to be used as a long-time test to find sporadic data transfer
A remark on the estimated time remaining: For intact flash memory the
estimate should be pretty exact since it has a constant data rate.
With defective media we have seen massive drops in the transfer rate
resulting in the estimate increasing instead of decreasing. Hard
drives are slower on the inner tracks than on the outer tracks so when
testing a hard drive the estimate is never precise.
usb flash drive capacity and speed software H2testw download