Colorbox plugin installed but status report is not recognizing it
Sometimes what happens with these libraries is that the download you get from the library site (colorbox in this case) packages its code in a folder itself. For the master download of colorbox, for example, the code comes in a folder called colorbox-master. If you unpack it into 

sites/all/libraries/colorbox 

then the code ends up in

sites/all/libraries/colorbox/colorbox-master

What you may need to do is unpack it into

sites/all/libraries

and then rename 

sites/all/libraries/colorbox-master

to be

sites/all/libraries/colorbox