There, frankly, I'm going to repeat myself because here is the 5th I buy. The whole family is entitled. This mouse is really great. It adapts to all surfaces, even the smoked glass. It is recognized by XP without problems, for Vista, by Seven and Linux (Ubuntu). Once the key inserted, the OS recognizes it and it works. Of course if you want to use all its features (4th and 5th programmable buttons almost at will), it will install the software available online but for which I have not yet found any bugs. In addition, the key is so small that it remains permanently on my laptop: she hardly beyond the rim of the lid and I've never hooked despite frequent travel. And the detachable wheel to scroll through the pages to 200 earlier: happiness. Pressing and presto, the notches return No, really, I strongly advise: buy eyes closed