Golly, I love Windows 10! 
WTF, I had my sharing all worked out, my computers were happy to play and work together. Then the new update comes out. Try to look at a folder from one computer to the other, nope. Not gonna do it, you have to enter the network credentials, which conveniently enough don't exist!
Insert long string of profanities here. No, keep inserting the profanities for a few more minutes.
Hmmm, the update renamed my workgroup to Workgroup. Change that back and I get sharing from computer one to two, but NOT two to one.
All I can figure is Microsoft wants me to play more games and forget about being productive on my own computers.