VST type: win 3 ??

I use the demo version of Cubase,
After I deleted some files with ccleaner software
Some effects that were used did not appear
In the insert{"no effect}, in spite of the dll files were still
Inside the VST library .
I checked What is common to all the files that disappeared, and all of them
Were of 2.2 and an additional marking of Win3 {I have no idea what that means}
I am more than pleased if anyone could explain to me what to do