If you were running the free version and then installed the paid ("Plus") version, did you uninstall the free before installing the Plus? If not, see reply #2 here and see if that gets it for you:
https://forums.wincustomize.com/376231
If that's not the case, when you post back include whether you are running the free or the plus and which version of Windows you're running (XP,Vista,Win7) and whether it's 32bit or 64 bit - that might give people more of an idea. Personally I don't think I've seen this particular thing come up before.
Also you might try disabling docklets to see if a docklet is causing a problem. OD Config/General on left/Trouble shooting Options button on right/ "Temporarily disable all docklets".