To run MidNote you need the runtime module of PocketC. You can get the runtime module for free, either from the PocketC homepage (www.orbworks.com), or (easier) follow below links to download version V2.0 (make sure you are connected to the Internet before clicking on them):

V2.0 Runtime For Handheld PC and Palm-sized PC (Windows CE 2.0-2.12)

V2.0 Runtime For PocketPC (Windows CE 3.0)