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My question is when we integrate on-premise AD domain with Azure AD, and our on-premise AD accounts are synchronized with AD, what will they be able to do without any license attached to it?
The Short Answer, yes
Will those account be able to login to domain computers
If the accounts exist on your Domain Controller, yes
can we enable MFA for them for domain computers login?
If you want to use the Azure AD resources, I think not. If you are already using MFA, it will not affect your methods of authentication.
Hope this helps,
Carlos Solís Salazar
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