2007 iMac won't recognise boot USB drives...

N

Nige321

macrumors newbie

Original poster

May 6, 2013

6

0

• Nov 22, 2013

• #1

I have a mid 2007 iMac.

I've created Mountain Lion and Mavericks USB boot drives on different USB sticks and neither will boot the iMac.

They WILL boot my 2013 iMac and my 2010 MacBook Pro...

The drives show up in the Contol Panel Startup Disk panel, but are not available when I boot using the Alt key...

Any thoughts?

Anyone!

Chhers

Nige

 

hfg

macrumors 68040

Dec 1, 2006

3,621

312

Cedar Rapids, IA. USA

• Nov 22, 2013

• #2

Try a PRAM reset, let it cycle through the "chime" 2 or three times before releasing the keys. Then try the boot manager again. PRAM reset seems to fix a lot of "boot problems".

 

TyPod

macrumors 68000

Nov 2, 2006

1,745

18

Minneapolis, MN

• Nov 22, 2013

• #3

PRAM is a good idea. Have you tried other USB ports on the iMac? I've re-installed ML on several 2007's using a USB drive with no problems.

 

N

Nige321

macrumors newbie

Original poster

May 6, 2013

6

0

• Nov 23, 2013

• #4

Mmmm

Tried the PRAM reset (Twice) with no luck.
ALso tried different USB ports.

There seems to be occasional posts about this all over the net, with various machines and versions of OSX.

Maybe try a third different USB drive...?

 

stroked

Suspended

May 3, 2010

555

331

• Nov 23, 2013

• #5

Does your 2007 iMac have 64 bit EFI?

 

MyMac1976

macrumors 6502a

Apr 14, 2013

511

1

• Nov 23, 2013

• #6

Did you reintroduce them to one another? I know I don't recognize people or things I don't see often.

 

N

Nige321

macrumors newbie

Original poster

May 6, 2013

6

0

• Nov 23, 2013

• #7

Does your 2007 iMac have 64 bit EFI?

Click to expand...

Apple iMac "Core 2 Duo" 2.4 24-Inch (Al) Specs
Identifiers: Mid-2007 - 24" - MA878LL - iMac7,1

Did you reintroduce them to one another? I know I don't recognize people or things I don't see often.

Click to expand...

Well that's a help...

 

N

Nige321

macrumors newbie

Original poster

May 6, 2013

6

0

• Nov 24, 2013

• #8

stroked said:

Does your 2007 iMac have 64 bit EFI?

Click to expand...

What difference would that make?

 

stroked

Suspended

May 3, 2010

555

331

• Nov 24, 2013

• #9

Nige321 said:

What difference would that make?

Click to expand...

All the difference. Google it.

 

N

Nige321

macrumors newbie

Original poster

May 6, 2013

6

0

• Nov 25, 2013

• #10

stroked said:

Does your 2007 iMac have 64 bit EFI?

Click to expand...

It must have, it's running Mountain Lion... Simply can't boot from a USB drive with ML on it... It can see it, it appears in the Startup Disk pane, but it doesn't boot...

 

P

paukivbashne

macrumors member

Sep 16, 2012

93

7

Ukraine

• Nov 25, 2013

• #11

I'm experiencing (almost) same issue with latest 2013 iMac
tried to install ML thru my usb stick that still works on everything except iMacs!!! ( i tried on 2012 model as well)
it showed up in boot menu as "efi boot" but when i go for it it shows me crossed circle
don't know what the hell does this means so i went with internet recovery (cmd+r) and installed it over internet