WD box keeps telling me authentication is wrong - It's not

Basically I could access all the files on my pc via the Shares - Network share - SMI route. I even saved my user name and password in there so it automatically authenticates. I moved the box from one room to another and although i can access files in e.g. Videos via the media server I cannot access anything via the shares. It keeps saying invalid user name/password.

I’ve even done a factory reset on the box but it’s made no difference

Any ideas? 

Edit: No idea what happened but it’s not working again…although I have a new issue (which i’ll post)

Wait, it is working again or not? Asking because what you stated in the edit part,