iTunes 12.2 broke the shared library feature from Mac to Windows My music is stored on my iMac, and I also have a PC with windows that I use for video games, I leave iTunes opened on my iMac when I'm on my PC so that I can listen to songs while gaming.

Here's my iTunes Sharing preferences on my iMac


The shared playlist appears on my PC, as you can see here


But clicking on it only shows a spinning indicator and then gives up after about 20 seconds, not showing the library on my iMac.


Yes, both iTunes versions are exactly 12.2 on each machine, and this only happens since 12.2. Sharing my library worked fine before this update.
Apple removed Home Sharing for music with 12.2. The theory I've read on the Apple forums is that this is one of the concessions they had to make with the music labels in order to get Apple Music off the ground. 

Here's a cnet article that mentions the feature change:

http://www.cnet.com/news/itunes-users-hit-stumbling-blocks-with-arrival-of-apple-music/

Edit: Home Sharing for music was indeed removed with the latest updates. 

http://arstechnica.com/apple/2015/07/eddy-cue-apple-working-to-bring-back-itunes-home-sharing-for-ios-9/