When you try to logon to computer on a domain, you may receive the following error "The trust relationship between this workstation and the primary domain failed"
Domain computers set up secure communications by using a computer account in the domain. For this to work, the computer account is protected by a password which is usually changed by the domain computer every 30 days.
If the computer account becomes out of sync - i.e. the password does not match for some reason - the domain computer will be unable to log onto the domain.
The account can go out of sync for a number of reasons including:
There are several possible methods to rectify this problem.
The first step would be to try and to reset the secure connection. From the Domain Controller, open Powershell or Command Prompt as an Administrator and type in:
Netdom reset ComputerClientName /Domain: DomainName
If the quick method doesn't work, then you will need to remove the computer from the domain, reset the account within Active Directory (see above) and then re-join the computer back to the domain.