It was working for a year and now it hangs on Melodyne vst3

I have used my current setup flawlessly for almost a year and now it hangs up. In a nutshell everything appears to be loading at the startup screen and then Cubase 5 Studio 5.5.1 hangs on loading melodyne vst3. The only change that I have made to my system in the last few weeks was adding Rayzoon’s new pack. However, I have used Cubase several dozen times since loading it.

Any suggestions on how to rectify this problem?

Here is my system:
Computer (Built By Me):
AMD Athlon 64 x2 5600
Gigabyte ga-ma69gm-s2h
4 Gig Memory

Windows XP Media Edition S3

TC Electronic Impact Twin
Novation SL MKII Controller

Steinberg Cubase 5 Studio
Rayzoon Jamstix 3 XXL
Celemony Melodyne Singletrack

When all else fails, trash prefs.