Problem Summary: cannot boot into motherboard BIOS: HP Compaq Pro 6300 MT + Windows 10 Pro x64

[MRFSYS]

Problem: cannot boot into motherboard BIOS: HP Compaq Pro 6300 MT, Windows 10 Pro x64

(1) flashed new motherboard BIOS to Version v03.08

(a) Shift+F10 keys only worked once, then stopped working
(b) what is recommended hardware combination, chiefly keyboard make/model?

(2) which keyboard key combination is correct to boot into BIOS?
(a) F10
(b) ESC
(c) fn key
(d) Shift + some other key(s)

(3) the Splash Screen only appeared once, then stopped appearing
(a) an HP brand USB keyboard did allow booting into BIOS, connected to front USB port

(4) do different keyboard brands make a difference?
(a) HP
(b) COMPAQ
(c) Dell

(5) is there a difference between USB & PS/2 keyboards
(a) my PS/2 keyboard uses a Linksys brand 2-port KVM switch w/ PS/2 connectors

(6) which keyboard sequence to boot into BIOS and change BOOT device?
(a) hold down?
(b) press & release?
(c) when to press / when to release?

(7) do inserted USB thumb drives block access to BIOS?
(a) Microsoft enforces policy of NO BOOTING from USB sticks

(8) do inserted WiFi dongles also block access to BIOS?
(a) see 7(a) above

[itsmyname]

> (5) is there a difference between USB & PS/2 keyboards

Yes. A PS/2 keyboard must be connected to a powered-off computer, to be detected at the next power-on time, while a USB keyboard can be connected any time when Windows is running. 

Some motherboards can be configured to NOT access the USB keyboard and mouse during power-on.

> (a) my PS/2 keyboard uses a Linksys brand 2-port KVM switch w/ PS/2 connectors

I would try connecting the PS/2 keyboard DIRECTLY to the computer.

Hint: with the computer powered-off, hold down any key on the keyboard. Power-on the computer while continuing to hold down that key. Do you eventually get a "keyboard error. Press <some_key> to enter BIOS SETUP" ? If so, release the held-down key, and press the indicated key.

[be_shameem_prog]

hi there,

restore your default settings for the BIOS, it resets the settings for the USB ports and they work correctly again.

Restore your default settings, and then select the option to set default values and exit.  Reboot, then go back into the BIOS to reset your boot on USB order and your USB ports should start correctly.

1-a)try Shift + Fn + F10 

 -b)check this link

https://www.microsoft.com/en-in/windows/windows-10-specifications

[be_shameem_prog]

2)The F1 or F2 key should get you into the BIOS. Older hardware might require the key combination Ctrl + Alt + F3 or Ctrl + Alt + Insert key or Fn + F1.
Go to Settings (Windows + I) > Update & Security > Recovery and under Advanced startup click Restart now. Note that this will actually restart your computer.
Windows 10 Recovery Advanced Startup
When you restart using advanced startup, you'll first get to choose your boot options. On the screen that comes up, go to Troubleshoot > Advanced options > UEFI Firmware Settings and click Restart, which will boot straight into your UEFI BIOS from Windows 10.

[MRFSYS]

Thanks for your help. 

In the HP documentation I had read to date,

some documents advise ESC,

some documents advise F10, and

some documents advise fn+F10 .

With time, I was able to access the motherboard BIOS

with a USB keyboard that also has an "fn" key.  However,

our other keyboards here do not have an "fn" key, and

we need to switch between 2 x HP PCs with an aging

2-port KVM switch that requires PS/2 connectors.

And, some of the USB-to-PS/2 adapters we have

in spare parts here, must be defective because

they have never worked.

After some trial-and-error, I did also upgrade the

motherboard BIOS to the latest version.

I'm keeping that "fn" keyboard handy,

in case we need to access the BIOS again

using the method that did work last time.

For now, the PC needing a solution is

working fine again (I'm using it to write this).

Thank you again for providing valuable options.

[MRFSYS]

Thanks for your help. 

I found it necessary to take a detour into the settings

configuring the integrated Ethernet adapter.

"Wake on Magic Packet" and "Wake on Pattern Match"

were both ENABLED.

Also, under "Power Management", there is a check box to:

"Allow this device to wake the computer" .

All of the latter appear to enable a "back door"

without my knowledge or consent.

And, in one HP document, I found an isolated reference

to "enabling remote access"  -- but I can't quite remember

the exact document where I saw that reference.

Further up the "chain of command" there are also

OS options to enable remote access for assistance

with troubleshooting:

In the "Remote" tab under System Properties,

at "Remote Assistance" and "Remote Desktop"

find:

"Allow remote connections"

AND

"Allow Remote Assistance"

As such, all of the above were suspects

in our search for explanations for the

failed USB cable to our APC battery backup unit.

These options got me wondering if this PC

was awakened by a "magic packet"

transmitted by some hacker who tried,

but failed, to take control e.g. to plant a virus

while I was asleep in bed.

[itsmyname]

> we need to switch between 2 x HP PCs with an aging 2-port KVM switch that requires PS/2 connectors.

I have a similar 2-port KVM that uses VGA & PS/2 connectors. A double-tap of "Scroll Lock" works as a selector.  Give it a try.

> some of the USB-to-PS/2 adapters we have in spare parts here, must be defective because they have never worked.

If the adapter is GREEN, it interfaces between a USB mouse and a PS/2-mouse socket.

If the adapter is PURPLE, it interfaces between a USB keyboard and a PS/2-keyboard socket.

And never the twain shall be mete.  🙂

[itsmyname]

> all of the above were suspects in our search for explanations for the failed USB cable to our APC battery backup unit.

Does APC recommend installing software on your PC, to monitor, via the USB cable,  the UPS?

> These options got me wondering if this PC was awakened by a "magic packet" transmitted by some hacker who tried, but failed, to take control e.g. to plant a virus while I was asleep in bed.

Any unsolicited packet coming from the Internet will be blocked by your cable-modem/router (or telephone equivalent), because the router will not know which of the computers on your LAN is expecting to receive that "magic" packet. So, the router will drop the packet; the hacker's packet won't reach your computer.

To send the packet, the hacker would need to have a computer inside your LAN -- which, by itself, is a security problem. Either that other computer on your LAN is virus-infected, or the hacker has physically connected (Ethernet) or  wirelessly-connected (obtaining your LAN's WiFi password) their computer into your LAN.

[MRFSYS]

>  Does APC recommend installing software on your PC, to monitor, via the USB cable, the UPS?

Yes:  all of our workstations are powered by APC UPS battery backup units.

The problem that surfaced initially was a failure of the USB cable

connecting our HP workstation and the APC UPS powering that workstation:

the APC "PowerChute Personal" software raised a warning flag in the task tray

indicating that it could not communicate to the UPS.

We tried enough different cables to support a conclusion that

it was the USB port on that workstation that was faltering,

NOT any of the various different cables we tried.

We also connected a different but identical newer UPS,

and the result was still the same error.

Eventually, the problem disappeared after I flashed

that workstation motherboard with 2 newer BIOS files

(the first was required before the second could be flashed).

[MRFSYS]

>  Eventually, the problem disappeared after I flashed

>  that workstation motherboard with 2 newer BIOS files

It was at that point in our troubleshooting that

I was unable to boot into the most recent BIOS.

In our spare parts inventory, I did find an older

HP brand USB keyboard with the "fn" key.

With that keyboard connected to a USB 2.0 port,

I was able to use that "fn" key with F10, and

that combination got me into the motherboard BIOS.

Happily, everything has now returned to normal

on that HP workstation;  and, yes we can alternate the KVM

switch between 2 workstations by hitting the "Scroll Lock"

key twice in a row.

And, we reverted back to an older Compaq brand keyboard

that has a PS/2 connector required by that older KVM switch.

Many thanks to everyone who has been generous

with their thoughts and recommendations above.