1. Checking to make sure midi cables are connected properly, and try different midi cables.

2. Use FreeMII's "Check Connections" to see if freemidi is receiving midi. If not, try making a new freemidi configuration.

3. If Freemidi Does work, go to the “basic” menu in DP and then to “Set Input filter” . Hit the “Clear” button , then the “Set All” button then close the window.

4. Trash FreeMIDI and DP Preferences: QUIT all applications, and open the System folder. Locate and open the Preferences folder. Inside the preferences folder locate "FreeMIDI Prefs" and "FreeMIDI Setup Prefs" -> throw both items into the TRASH. Locate the Digital Performer folder inside the Preferences folder, and TRASH the "Preferences" file.
Restart your computer. On restart, open you FreeMIDI Configuration -before- opening DP.