I try to install Mountain Lion and I can't. It says "This disk cannot be used to start up your computer"

I have no idea where you're trying to install Mountain Lion but you need to make sure the partition is formatted with the GUID partition table and Mac OS Extended (Journaled). Otherwise, you can't boot from the partition.

See this Lion article (Apple hasn't posted a Mountain Lion version yet): http://support.apple.com/kb/TS3926

I have the same deal here. I was going to try the 'Lion fix' but I have a boot camp partition and I'd rather not make my small partition smaller. Also, I read on another site that it didn't work for someone. Hopefully there's another fix?

Apple...please help!

Apple isn't here.

This is a user to user forum.

Allan

gridsnap wrote:

I have the same deal here. I was going to try the 'Lion fix' but I have a boot camp partition and I'd rather not make my small partition smaller.

Did you see where it says "The partition only needs to be approximately 128 MB smaller"?

If your OSX partition is so tiny that 128 MB makes any difference, you've got much bigger problems.

wow. no patience for newbies here, huh?

@Allan Eckert...SORRY didn't realize this is a user forum ONLY and Apple doesn't read these.

@Pondini...SORRY didn't read that part about the 128 MB...did YOU read that I read on another site that it didn't work for someone? So that's why I didn't read the whole article. I will be more careful to do so next time so as not to get flamed. I only have a 256 GB SSD, so yeah, I do have bigger storage problems.

gridsnap wrote:

wow. no patience for newbies here, huh?

It's not that you're a newbie, it's that you just dismissed the advice.

And, like many others, I've been helping folks here for the better part of 14 hours today. And we're all volunteers.

did YOU read that I read on another site that it didn't work for someone? So that's why I didn't read the whole article.

Everything doesn't work for someone. Don't put a lot of stock in what one person may say -- he/she may have done it wrong, or there may have been an entirely different cause.

I only have a 256 GB SSD, so yeah, I do have bigger storage problems.

You are seeing 128 MB, not GB, right? That's 0.05% of 256 GB.

Dear Monsieur Smarty Pants,

I didn't dismiss the advice, I analyzed the advice and decided that an install workaround for a previous system update that may or may not work (you didn't actually say whether or not it HAS worked for anyone trying to install Mountain Lion) wasn't my best course of action.

I don't understand the hostility and condescendence, it wasn't like I said "hey idiots, I don't like your advice and I don't have any room on my hard drive!", I re-read my post and it was pretty mild.

Maybe you've been 'helping' too much today and should take a break or go to sleep.

Sincerely,

"Dumb *** guy who has a problem and dared not to take the first advice given to him"

Sorry that didn't add to the conversation. Won't happen again.

Keep Calm and Carry On. 🙂

gridsnap wrote:

. . .

I didn't dismiss the advice, I analyzed the advice

That's not what you posted earlier: "So that's why I didn't read the whole article."

you didn't actually say whether or not it HAS worked for anyone trying to install Mountain Lion

That's true, I didn't. I've posted that several times today; most folks never report back, but 2 or 3 did say it fixed it for them. YMMV.

I don't understand the hostility and condescendence, it wasn't like I said "hey idiots, I don't like your advice and I don't have any room on my hard drive!", I re-read my post and it was pretty mild.

You didn't use those words, but that was the gist: "I'd rather not make my small partition smaller"

Oh, by the way, the "Lion Fix" didn't work for me. In my particular case:

"Partition failed with the error:

File system resize support required, such as HFS+ with Journaling enabled."

So it appears that I do have bigger problems.

dude...you really need to have a beer or a joint.

You really took the whole tone of my original post too hard and personally. Take a deep breath and say "Not everyone is mad at the world."

I was drafting advice on the "File system resize support required, such as HFS+ with Journaling enabled" message, but I guess it's not worth the effort.

For many years Pondini has offered sage and welcomed advice and instruction in the Apple user forums. It's been a long hot day across most of the country. Let's keep our focus on the problems we are trying to solve.

I had the same problem earlier.. Finally, after several attempts...

1. Create a new partition (mac os extended journaled - don't make it too big - i used 128gb)

2. Erase free space of that new partition (fastest is fine)

3. Reduce partition size of the original mac hd (approx 128mb.. Could be more)

4. Re-install mountain lion and it should work (hopefully)

I think you can interchange step 2 and 3.. Probably doesnt matter but the key step is to erase the free space

Prior to the steps above.. I spoke to apple care and they asked me to verify disk and verify disk permissions.. Not much help since they both resulted ok (some minor permission warnings but not really a problem - i hit repair disk permissions)

Partition map should be GUID something.. forgot what it's called

Good luck!