Do you have msvcr120.dll and libeay32.dll in DiscU folder?
I had the same error with NUSGrabber, it was fixed with installing VCredist (and with the correct/missing vcruntime140.dll)
if you installed VCredist but it still error, try copying NUSGrabber's vcruntime140.dll to your folder. (in case it's related to that dll too)
Note that I don't have vcruntime140.dll in DiscU folder and it's working fine. I only installed latest VCredist x64 (on W7 x64)