Hello JG,
Thank you for posting in Q&A forum.
Is your old work account that was deactivated the PIN you mentioned? If so, because the PIN was deactivated, you can not sign in using the PIN.
Is the machine in domain or workgroup now? If it is in domain, you can try the domain user account in your previous company.
If it is in workgroup. Did you have local user account or local Administrator account on this machine? If so, you can sign in using one of the local accounts.
Hope the information above is helpful.
If you have any question or concern, please feel free to let us know.
Best Regards,
Daisy Zhou
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