It probably just has some dirt in it... Press and hold the mute button at the top of the device to put it into standby more. Now really press down on the trackball and work it around. This typically loosens up the dirt and funk. Press the mute button again to take it out of standby. Does it work now?
You may also want to try a can of compressed air and blow it out.
This morning my trackball stopped working also.
I can scroll sideways but can't move up or down.
The trackball isn't dirty but I cleaned it anyway and it's still not working
well as i havent ran into this problem myself. i remember reading a thread that said they used a compressed air to remove the dirt. he also said that you should do it with the face facing down. i cant remember the specific thread. you might want to look for it. hope that helps.
Ok, I had this problem with my 8830. I tried everything, and none of it worked. So, I took it into the Verizon store, and since I was still under warranty, they gave me a brand new unit. They said the problem was most likely due to the amount of times I had dropped the phone. Have you had a big drop recently? That could be your problem. Hope that would help.
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