Im running windows 8.1 64bit as well and that up there fixed my problem. Ill tell you exactly what I did but keep in mind while i tell you the steps I was desperate and reading 100 things at once and this is what i narrowed it down to.
1. Uninstall bonjour (you can just use apple update to reinstall it after)
2. Right click your itunes icon properties> compatibility> run itunes as administrator.
3. Followed steps from previous post.
4. Used apple update to update to current version and reinstall bonjour. (Keep in mind when i say current version I was only one version behind the current update)
And that worked for me. No more ysloader or disnoted32 running the cpu up. I also stopped running itunes as administrator after and it is still working. Maybe try deleting bonjour and reinstalling, who knows, but those are the steps i put into action tonight and thats how i solved the issue. Sorry if that doesnt help.