Cannot see WIN 10 startup page

[FuzzyLion]

I cannot get to either the boot menu or the WIN 10 login page.  When I hit the start button, the only thing that pops up is a small box that asks for user  password or administrator password.  It will only accept 8 characters for either of them and unfortunately both of my passwords have more than 8 characters.  Holding down any of the  f keys upon startup (or  hitting them repeatedly) has no effect on the outcome.  No matter what I do, I am stuck with this  box.  Is there any way to reinstall WIN 10 under these  circumstances?  All data are stored elsewhere so that is  not a consideration.

[Riddle_Decipher]

@FuzzyLion Thank you for posting on HP Community,

For an accurate solution I'll need more details:

What is the product number of your device? Use this link to find it: click here 

(Ensure you do not share any of your personal information such as serial, phone number, email ID, etc.)

Have you attempted any steps on your own before posting on the HP Forums?

When was the last time it worked without these issues? 

Did you run a hardware test on the computer using the F2 key during a restart?

In the meantime, please try the steps mentioned on this link: Click here

Please reply with the details for further assistance.

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