Cubase 4 prjts containing korg vsti's using synchrosoft?


I’m having trouble opening Cubase 4 projects in Cubase 6 that contain versions of Korg Legacy Digital which at the time used the synchrosoft usb for protection. The latest versions of the Korg Legacy Digital software have now changed to a software challenge and response key system. When I attempt to open this project I just get an error which states that the protection cannot be found and so it force closes the program.

I think I have removed all remnants of the old versions but maybe this was not the right thing to do in light of what I am trying to achieve now. i.e. open the old C4 version with the old Korg Legacy Synth used in the project. Does this mean that the only way I can open this project is to reinstall the old synchrosft version (if that’s still possible?)

Specs from memory:

Cubase 6.05 (i think. Latest paid for update.)