I can't login when my mac ask for: Enter your name and password for the server "WDMyCloud.local."

I can enter as a Guest but not as a Registered USer.

I’m running myCloud (not myCloud Home) any idea?

I’ll appreciate your help.

Have you recently reset the MyCloud? This will clear the admin password. If you haven’t, try pressing reset for 4 seconds. Your admin user name will stay the same, but the password will be cleared. The unit will be set to DHCP. Your data should not be affected. Refer to the Appendices of the User Manual.