Disabling the Built-in Administrator account in Active Directory should not directly cause a trust relationship issue between domains. The Built-in Administrator account is a local account on each individual domain-joined machine and does not have a direct impact on domain trust relationships.
Trust relationships between domains are established at the Active Directory level and are primarily based on the domain trust settings configured in Active Directory Domains and Trusts. The trust relationship allows users from one domain to access resources in another domain, and disabling the Built-in Administrator account on a specific machine won't affect this trust.
However, it's essential to note that the Built-in Administrator account is a powerful account and should generally not be disabled or used for regular day-to-day tasks. Disabling this account might cause issues if it was being used for specific tasks on that particular machine, especially during troubleshooting or recovery scenarios
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