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Windows 7: An operating system was not found.

08 Nov 2014   #1

Windows 7 Professional 64 bit
An operating system was not found.

I have an acer 5560 notebook with Windows 7 professional installed. I do not have any disks with the laptop as it is a second hand one. I tried to repartition my drive and once i finished, I put the laptop on hibernation. However now when I try to open it, it says An operating system was not found. Try disconnecting any drives that don't contain an operating system. I am not sure what to do. Alt+f10 doesnt seem to work either.

My System SpecsSystem Spec
08 Nov 2014   #2

Windows 7 Ultimate Retail Box (64-bit installed) + Service Pack 1

The error with no OS:

You mean powering it up from scratch NOW or just after this hibernation back to normal attempt?

Remove power to it for 10 secs and then try it again and post results please.

...Making sure first it was not just a snafu on hibernation. [a mode I avoid myself]

If you somehow partitioned your way out of the drive being properly setup to boot, you'll likely need to download a Windows 7 image (same version you are using) on another PC and burn it to a disc, then boot from it.

They can be found here:

You need that disc to do the repairs on 7, see the tutorial on this issue, if needed, found here at Seven Forums:

Startup Repair

Via repartition process, it's possible it trashed the master boot record or boot partion or file, that's most likely what happened.

Worse case scenario is you make it a linux box instead, if the OEM Windows is totally hosed and new OS is needed and you don't want to pay for another Windows install, I am threating to do that to a used laptop I bought 3 years ago, myself, if the HD fails, has Vista 32-bit. 8( hehe
My System SpecsSystem Spec
08 Nov 2014   #3

Windows 7 Professional 64 bit

Powering up from scratch. I have been trying to open it for the past 3 days.
My System SpecsSystem Spec

08 Nov 2014   #4

Windows 7 Ultimate Retail Box (64-bit installed) + Service Pack 1

So the laptop goes through POST? (power on self test)

OK, you'll need to get that exact 7 version's install DVD image burned, to boot to and follow the repair tutorial.
My System SpecsSystem Spec

 An operating system was not found.

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