I was trying to join windows 7 machine into our company Samba domain. after joining the computer i'm not able to login using a domain user name. i got error message "the trust relation between this workstation and the primary domain failed" How to fix this problem?

I would tend to think that you should probably post this question on a Samba forum. However, If this was an Active Directory domain, you can easily fix this by simply rejoining the computer to the domain. There are several reasons that cause this to happen. Visit: anITKB.com, an IT Knowledge Base.