First when looking at ReachUC, if you look in the top left hand corner of the dial pad page, you will see the "ReachUC" logo in green. There is where it will show if you have new voicemail messages or not. If you do, simply type in 5001 in your key pad and dial it, it will prompt you to put in your voicemail password followed by the "#" key. Then you will be able to hear your messages.
Also if you do have a message, a blue voicemail icon will appear on the dial pad page.