I'm having problems when running the write test of HD Tune Pro. The flash drive i use is Lexar 8GB. Here is a screenshot of the error: http://s7.postimage.org/cjxdvlsyh/fdfadfaddaf.jpg
I tried writing tests with other software and everything was fine, but I need to use HD Tune Pro now. Unfortunately I don't have other flash devices arround me to tell you if that happens with them too.
Unfortunately I don't have an answer to your problem, except to say that I have experienced an identical issue using HD Tune on two different flash drives - a Patriot Xporter XT 8 GB, and Verbatim Save 'n' Stay 16 GB. Have no idea what it means. Both USB drives operate without any problems. Hopefully somebody can shed some light on this.