HP ProDesk 400 G1 Maintenance And Service Manual page 171

Nonsystem disk/NTLDR missing message.
Cause
Bootable hard drive is not attached as first in a multi-hard
drive configuration.
Bootable hard drive is not listed first in the Boot Order.
Computer will not boot from hard drive.
Cause
The device is attached to a SATA port that has been hidden in
Computer Setup.
Boot order is not correct.
Hard Drive's "Emulation Type" is set to "None." (some
models)
Hard drive is damaged.
Computer seems to be locked up.
Cause
Program in use has stopped responding to commands.
Solution
If attempting to boot from a hard drive, ensure it is attached to
the system board dark blue SATA connector.
Run the Computer Setup utility and select Storage > Boot
Order and ensure the bootable hard drive is listed
immediately under the Hard Drive entry.
Solution
1. Check SATA cable connections.
2. Run the Computer Setup utility and ensure Device
Available is selected for the device's SATA port in
Security > Device Security.
Run the Computer Setup utility and change boot sequence in
Storage > Boot Order.
Run the Computer Setup utility and change the "Emulation
Type" to "Hard Disk" in the device's details under Storage >
Device Configuration.
Observe if the front panel Power LED is blinking RED and if
any beeps are heard. See Appendix A,
on page 190 to determine possible causes for the blinking
red and beep codes.
See the Worldwide Limited Warranty for terms and
conditions.
Solution
1.
Use the task manager to close programs that do not
respond.
2. Attempt the normal Windows "Shut Down" procedure. If
this fails, press the power button for four or more
seconds to turn off the power. To restart the computer,
press the power button again.
Solving hard drive problems
POST error messages
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