Installing Mac osX on erased HD

uhmm... many ways. sounds like your superdrive is bad

simplest but perhaps most time consuming would to take it to an apple store, they will image your drive via USB/Firewire or Ethernet

alternative suggestion could be:

target disk that macbook to another mac, install desired OS with optical drive of other macbook is one.

I agree that your optical drive may be bad, or you may have a corrupted install disc. It's also possible you didn't properly seat the optical drive connection. I'd check the disc in another Mac to make sure it's good and, if it is, re-seat your optical drive connection.

Installing an OS on a completely erased HD shouldn't be a problem at all. So that's definitely not an issue.

Try getting a USB flash drive and copy down OSX onto it and then boot up the computer with it and install it that way, this way you can make sure if your optical drive is the problem or not too.

I'd look into reseating the memory modules and try them one at a time while installing via the optical drive too, just to make sure the memory modules aren't faulty, because if they are, they can make all sorts of problems, like the one you are experiencing. Always worth a try.

M Quick said:

I'd look into reseating the memory modules and try them one at a time while installing via the optical drive too, just to make sure the memory modules aren't faulty, because if they are, they can make all sorts of problems, like the one you are experiencing. Always worth a try.

Click to expand...

Poorly seated RAM CANNOT cause a flashing question mark. That only appears when the firmware can't find a valid system to boot from. Reseating the RAM is a good idea if you are trying to eliminate all possible issues, true, but it can't cause the issue OP is experiencing.

iThinkergoiMac said:

Poorly seated RAM CANNOT cause a flashing question mark. That only appears when the firmware can't find a valid system to boot from. Reseating the RAM is a good idea if you are trying to eliminate all possible issues, true, but it can't cause the issue OP is experiencing.

Click to expand...

Is that a bet?

And the firmware is located, where (physical)? And via what way does the firmware reach the hard drive to read it's state?
I would agree with you if the RAM wasn't such a vital hardware to start a computer with, but it is and i know that different failures of bad RAM modules are gonna give you different problems/errors.

Ask me how i know..

M Quick said:

Is that a bet?

Click to expand...

So you personally have gotten the "valid OS not available" error from poorly seated RAM? I find that hard to believe. If you did, it was a fluke and your Mac was not acting the way it was designed.

It seems you have been given some bad advice which has confused the situation further - the MacBook Air external SuperDrive will not work with the MacBook, it has a custom board inside which will only talk to the MacBook Air.

I believe any DVD external USB drive ought to be OK, except, unfortunately, the Air external.

iThinkergoiMac said:

So you personally have gotten the "valid OS not available" error from poorly seated RAM? I find that hard to believe. If you did, it was a fluke and your Mac was not acting the way it was designed.

Click to expand...

I have no idea what experience level you have with computer hardware in general, so i'm not gonna judge you, but;

Poorly seated RAM? No.
A bad RAM module? Yes.
Fluke? Yeah sure, a bad RAM module can, depending on how it have failed, create many different problems/flukes, probably more than you might think.
If you understand how RAM modules communicate via the north bridge/mch (memory controller hub), you will also understand how it can affect the other hardware in the system when it has failed. Just saying..

A poorly seated RAM module would not even boot up the system btw.

bcatwell said:

I hate hearing that! But thanks for the response. Is there an external cd drive I can purchase that my MacBook will recognize?
Thanks

Click to expand...

You can, luckily mod your air superdrive so that it will work with any machine, you can get this part from ebay for about 5bucks and up. Google how to mod the air superdrive and you'll know how to go further with it, that is if you can't exchange it for your money back and you're stuck with it, or if you really want to keep it because of design reasons..

Then return it and get any other (non apple) external optical drive to go, it's funny how apple sells these optical drives that is locked to only work with a specific laptop, and i guess the price is above average for any other brand too, which is ridiculous imho. I've only tried branded (samsung and LG for example) external optical drives, and they have worked just fine, plug and play. Works on all laptops mac and windows pc's. And they are cheap too.

bcatwell said:

It just occurs to me that getting my MacBook to recognize the external drive without any OS installed could be a problem.

Click to expand...

Won't be an issue, firmware will take control of that. Think about it: if you boot an OS X install DVD from an external drive, did the OS on the internal drive ever load?