Fix Invalid trust relationship

Reset-ComputerMachinePassword -Server DomainController -Credential DomainAdmin

    Server – the name of any domain controller;
    Credential – a domain user (with permission to add the computer to the domain) or domain admin account.
	starting with Windows 8/Server 2012
	on Windows 7, Server 2008 and Server 2008 R2 requires PowerShell 3.0 & Net Framework 4.0+

Netdom resetpwd /Server:DomainController /UserD:Administrator /PasswordD:Password

    Server – the name of any domain controller
    UserD – username with domain admin or delegated privileges
    PasswordD – admin password
	Netdom is part of RSAT (Remote Server Administration Tools) package.
	https://www.microsoft.com/en-us/download/details.aspx?id=45520

	This method does not always work, because it is not always possible to authorize on the domain controller under the administrator account from a computer this broken-trust relationship.

Nltest /sc_change_pwd:corp.Contoso.com

	This command will try to repair the secure channel by resetting the password both on the local computer and on the domain computer, and it doesn’t require domain rejoining or rebooting.

However, unlike Netdom and Reset-ComputerMachinePassword, which allow you to specify user credentials, Nltest works in the context of the current user. Accordingly, if you logon to the computer under the local account and attempting to execute the command, you will receive an access denied error. Because of this, the method doesn’t always work.

https://theitbros.com/fix-trust-relationship-failed-without-domain-rejoining/
how to howto fix a failed fail broken trust relationship with without out domain joining rejoining