First of all: try resetting the plugin info in cubase. If that doesnt work, rename your vst plugins folder and run cubase again.
Open the vst plugin menu in cubase and add the new renamed folder as your shared vst folder, and restart cubase.
if that doesnt work:
That means ( to my knowledge) that you have the dll files in your xtc folder, but that your xtc config file( forgot the name of the config file..) has wrong directories..
I dont know what you have and havent done, but this is what you need to do if i remember right:
1:Install scope with xtc mode.
2: create a folder inside your scope directory called XTC PLUGINS ( you decide) EG: C:/scope 4.5/devices/xtc plugins
3. open up the xtc configuration file in a text editor ( I think its called "vst config" and its located in some sub sub folder.. sorry about this but i cant remember, maybe someone else can help with the actual file name)
- In this file you should se a row of directories. One with the words mono in front of it and one with the words stereo in front of it.
Copy these two ( mono and stereo) text lines, and insert them in the bottom, right after the last line and edit them so they contain the path of your xtc folder.
EG:
ScopeMono C:/scope 4.5/devices/xtc plugins/*.*
and Scopestereo C:/scope 4.5/devices/xtc plugins/*.*
( i think that this is the same wording that is used in the file)
4. Go to your shared vst plugin folder, and pick a plugin that you know is working.( any plugin. not a creamware one) and copy that into your XTC folder EG:
C:/cubase/vst plugins/XTC
make as many copies as you need XTC plugins.
Now rename every single one of the copied plugins to match the names of the plugins in your C:/scope 4.5/devices/XTC plugins/ folder. but leave the DLL extension
example:
was supercomp.dll now renamed to minimax.dll
was supercomp.dll(2) now renamed to masterverb.dll
etc etc..
the actual dll files in your c:/cubase/vst plugins/ folder are actually not used at all.. they are just "shadows" of the files from the c:/scope 4.5/devices/xtc plugins/ -folder
5. edit the xtcproject located in some other sub folder

to suit your needs. save it.
6.start cubase
Open the vst plugin menu in cubase and add the c:/cubase/vst plugins-folder as your shared vst folder, and restart cubase.
IF that doestn work, rename the vst plugins folder to something else, set it up in cubase and restart cubase again.
I know this seems like an awful lot, but when you get the hang of it, it is actually really easy..