Windows 8.1 & Mac OS X (Yosemite) Samba Share Fails

Hello everyone,
My basic issue is that my Windows machine fails to connect to a Mac samba share with known good credentials - rejected name and password, no permission to access.

The weird thing is that this just started happening for the first time two days ago. I made no system changes over that period, and connections were working smoothly before that. The other strange thing is that my co-workers PC (also running Windows 8.1) still works perfectly... and I can access the share from that machine with my credentials. And I can even access and see files on my PC from the Mac. So I think I have narrowed it down to something on the windows side, specific to my computer.

Things tried:
I've been doing research for the past few days of course, and am only posting before exhausting all other options. The main things that people purpose a fix is by changing several of the network security policy setting. None of those have made any difference unfortunately. Also tried uninstalling and re-installing my network adapter. Clearing all Netsh & DNS caches. No dice.

Any ideas would be much appreciated!

You would be best to go to support.apple.com regarding the issue with Mac OS-X not sharing through Samba to the Windows computer.

Samba is a finicky program for any Linux distro. You could try the latest update from samba.org. If you are running a firewall on either the Windows or Mac OS-X machine, try turning it off. Same with any Internet Security software.