Arpeggiator Problem SOLVED!

Could be a messed up registry entry. For X3 Producer check registry path HKEY_CURRENT_USER\Software\Cakewalk Music Software\SONAR Producer\X3\UserPaths key ArpPresetFolder. ArpPresetFolder should point to the "Arpeggiator Patterns" folder containing the .ARP files.
 
 

That does not sound like the "Arpeggiator Patterns" folder but it could be if that is how you set up your system. I believe the default location is "C:\Cakewalk Content\SONAR X3 Producer\Arpeggiator Patterns". Since the Cakewalk Content location is defined during installation the ArpPresetFolder registry entry needs to reflect the location of the arp patterns on your system.

To edit the path in the registry key ArpPresetFolder double-click the key

Now if only I could change my avatar