To help translate what is going on there, the mass of errors are all saying "the SSLeay code referred to a piece of OpenSSL named XXX but now that it's time to combine the compiled code of SSLeay with OpenSSL we can't find that named thing". Since there are so many things it can't find, it probably didn't find libssl-1_1.dll at all. The reason it might not find the dll at all was if it wasn't looking in the right place. The list of places it looks are all the directories starting with -L on the command line. If your OPENSSL_PREFIX is not in that list, then something went wrong with building the Makefile. Maybe start from scratch after defining the prefix variable?