Trusted Domains count not authenticate users

[RM]

I have created trust between domain A & B and when I want
to join the domain B with a user from Domain A erron comes
up as "unknown user or bad password "

Anyone can help please.

 

[Trying to help]

Sounds simply, but sometine happens:are you typing well
the password and username? Try using another account.
Also, check/verify the trusts between Domain (Active
Directory Domain & Trusts)

 

[RM]

Thanks. but does not work. the trusts were already been
varyfied.