Recover deleted main OS in boot manager

[Yassine17]

Hi I accidently deleted my Windows 7 home on the boot menu it's the main OS , when start my pc the boot manager appear but the choice "windows" to choose isn't  shown and stiil forever at the boot manager! So I can't access to Windows.

Please I need your help to enter windows without formating because I have important files in the hard disc ! Urgent 

[Lil_Boy_Blue]

Hi

My suggestion is to make a DVD/USB with the W7 OS on try something like....

This First part only works when a valid Recovery Partition is enabled.

If it displays an error message then move onto the Second part,
OR if you have data you wish to try and save using the XCOPY command.
Then create your own Repair/Recovery/Rebuild/Re-install media or buy a set from HP.

Turn off the computer.

Disconnect all connected devices and cables, Media Drives, USB drives, printers, & faxes.
Remove media from internal drives, and remove any recently added internal hardware.
Do not disconnect the monitor, keyboard, mouse, or power cord.

Turn on the computer and repeatedly press the F11 key, about once every second,
until the Choose an option screen is displayed, and then continue.

On the Choose an Option screen, click Troubleshoot, and work your way through the screens.

Second Part:-
This may require another PC. Find and Download your .iso from…
You will need a NON_OEM key for W7.

https://www.microsoft.com/en-us/software-download/windows7
A 3rd party site like…
https://www.heidoc.net/joomla/technology-science/microsoft/67-microsoft-windows-iso-download-tool

Expand/Extract/Burn the iso Image onto a DVD/USB as needed.

Even though it has NO actual HP software/drivers included, you may be able to
XCOPY the C:\Users\* area onto a ‘large’ USB stick, via the Command Prompt.

You’ll need to try various drive letters; D:..-..Z: until it’s matched - could be G; mine’s S:

C:\>XCOPY C:\Users\* S:\ /e /i /h (then files like those 3 listed below get copied over)

C:\Users\desktop.ini
C:\Users\All Users\agent.1509128044.bdinstall.bin
C:\Users\All Users\HP Deskjet 2540 series\Help\flash\zoom.swf

Then you can try System Recovery Options / Advanced Options shown in the screenshots.

NB:- W7 Try running a Startup Repair more than once for a full fix.

From either the C:\ or the X:\ prompt try the following

cd boot
bootrec /FixMBR
bootrec /FixBoot
bootrec /RebuildBCD

If the above FAILS then please try:-
http://www.thewindowsclub.com/repair-master-boot-record-mbr-windows
http://www.thewindowsclub.com/install-windows-7-from-usb