So Seth Goldin on the Apple forum has gave us a solution but I think WD might need to investigate this signing business.
Here is a direct link to Seth Goldin post https://discussions.apple.com/message/30287193#30287193
and here is my step by step procedure on a Mac
- start up terminal
- cd /etc
- sudo vim nsmb.conf
- type in your password
- while in edit press the letter i for insert
- copy and paste the following text
[default]
signing_required=no - hit esc, then the colon : to get to the command line, then type wq [enter]
- reboot your mac
- now a standard mapping of SMB will work as before.
