I bought a Transcend memory stick and tried to use it in my mac. The stick is described as compatible to OS X but I was not able to use the stick out of the box.
This is caused by the stupid software which is installed on my stick. First of all the stick is write protected and Transcend installed a Trend Micro Virus Scanner which is mounted as CD drive.
The removal of this combination took hours of my time.
After searching around i found the solution on seasonsecurity.com where it is described in this thread>>