Most are locked so that user resets are not possible to combat theft.
Since the Acer is NOT at https://bios-pw.org/ you are looking at 100 bucks to have Acer unlock it. This is probably why the machine was stripped of the HDD. Without the HDD there is NO WINDOWS in the laptop so any Windows issues don't apply.
Longer explainer at http://www.tech-faq.com/how-do-i-reset-an-acer-bios-password.html
Since this is not a desktop you are stuck with paying Acer to unlock. Why can't the owner tell you this or unlock it for you? Sadly half the time I discover the laptop was stolen or "I found it."
Hi Was given awhile back a ACER Aspirer E 15 laptop with no disc or a flash drive .When I turn it on it ask for a current password that was not given how can I open this laptop so I can reset pass words ?Am to believe is windows 10

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