Exchanged HDD in MacBook Pro - OS X installation disk shows prohibitory sign I exchanged the HDD in my 2007 MacBook Pro and removed the DVD drive because it was making a terrible noise every time I booted the MacBook.

The new HDD is a Corsair Force F120 SATA SSD. I formated it as HFS+.

Every time I try to launch an OS X Lion installation disk or USB stick I get the grey prohibitory sign and the machine shuts down after a while.

When I connect the old harddrive (with OSX still on it) I'm able to boot it up successfully.

Any ideas what is wrong?
it is greyed out because it is in the wrong file format => ntfs

you should use disk utility via the usb stick to format the drive to HFS+ and then you will be able to install on it