I bought a replacement mouse for the previous Microsoft Compact Optical Mouse 500 v2.0 that I had because I like the model. The first mouse I had was plugged into one of the USB ports on the right side of my laptop and it worked perfectly fine. Yesterday I began using the replacement mouse (remember, they're the same exact model) and it wouldn't connect in either of the USB ports on the right side of my laptop. Fortunately it works when plugged into the USB ports on the left side but the cord is so short that is very difficult to use. It also lies completely across over my keyboard making for an annoying and uncomfortable usage. The only thing that I've done to my laptop recently is clean the dust from the fans. My external HDD worked fine when I plugged it into both USB ports on the right side so I don't know what the problem is.