Can I Ever Get OS X Back?

[MacFan23]

So I've managed to get myself into a bit of a situation. A while ago I intended on giving my dad my old MacBook Air (11inch 2010 model) however he only uses Windows. I installed Windows 7 on the machine then proceeded to delete the OS X partition. I now want to reinstall OS X but I'm having some problems. Nothing seems to work. I've tried alt-booting and Cmd-R booting but each results in the command being ignored and the air booting into Windows. Any advice out there? Feeling a bit foolish now

 

[GimmeSlack12]

So you don't have a rescue partition anymore either? You will likely need the thumb drive OS X install and boot holding option down.

Does the Windows BootCamp control panel offer any help?

 

[mmomega]

The 2010 models should have come with a recovery USB drive, use that to reinstall.

Tried holding option before boot sound?

Next option, download Lion, ML or whichever OS X you were using on another Mac and use LionDiskmaker to create a new bootable USB drive, 8GB USB minimum.

 

[Weaselboy]

2010 should have firmware that supports Internet Recovery.

Try a command-option-r boot and see if you get the spinning globe for Internet Recovery. Once loads the recovery screen use Disk Util to erase the entire drive then install the OS.

 

[MacFan23]

None of those seem to work :/
The screen just stays white for a while then boots into windows as if I hadn't been holding down any keys, as if it can't access the firmware.

 

[Weaselboy]

None of those seem to work :/
The screen just stays white for a while then boots into windows as if I hadn't been holding down any keys, as if it can't access the firmware.

Do you have access to another Mac? If so, you can use a 1GB or larger USB key along with this Apple utility to make yourself a boot key that will allow you to recover. It will need to be the same version as whatever OS version you want to install.

 

[MacFan23]

Do you have access to another Mac? If so, you can use a 1GB or larger USB key along with this Apple utility to make yourself a boot key that will allow you to recover. It will need to be the same version as whatever OS version you want to install.

Unfortunately holding down the Alt key is not recognised, so I can't boot from the recovery drive

 

[Nermal]

2010 should have firmware that supports Internet Recovery.

Only if it's previously been installed.

OP: Are you using the MBA's built-in keyboard? Do you have any USB devices connected?