-2101F error

Hi there ayhanselek,

It sounds like you are trying to erase the content of your hard drive to reinstall Mac OS X but you get this error code when you try. That may indicate that there is a hardware issue with the drive, but I would start by resetting the PRAM on the computer and trying again:

How to Reset NVRAM on your Mac

1. Shut down your Mac.
2. Locate the following keys on the keyboard: Command (⌘), Option, P, and R.
3. Turn on your Mac.
4. Press and hold the Command-Option-P-R keys immediately after you hear the startup sound.
5. Hold these keys until the computer restarts and you hear the startup sound for a second time.
6. Release the keys.

If that doesn't resolve it then I would next reset the SMC on the computer then test it out again:

Resetting the System Management Controller (SMC) on your Mac

If the issue still isn't resolved I would next try repairing the drive with the Disk Utility:

Repair a disk

Now if nothing gets it going again then I would suggest taking your computer in for service:

Service Answer Center - Mac notebooks

or

Service Answer Center - Mac desktops

Thank you for using Apple Support Communities, all the best!

Hi,

try connecting the power cable and pressing Command-R when restarting the machine to reinitiate Mac OS X installation.