Had this problem since Monday. Doubleclick on CC icon -> nothing happens.

Several reinstalls and reboots didn't help.

I finally got it to work after complete uninstall (incl. data) and then *manually* cleaning up the registry.

So whoever is responsible for this, please investigate if you can also remove those keys on uninstall:

HKEY_CLASSES_ROOT\.cwui
HKEY_CLASSES_ROOT\psyn
HKEY_CURRENT_USER\Software\CurseClient
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\MenuOrder\Start Menu2\Programs\Curse
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Management\ARPCache\CurseClient