[Leica] Cannot upgrade M8 firmware

[geordiepete211 at yahoo.co.uk (Peter Cheyne)]

Thanks for lots of double-check advice, guys.

I haven't had a chance to try it in another computer yet.  Basically,  
none of my Leica formatted SD or SDHC cards can be read by my card  
reader.  I have two card readers.  Both can read my Lumix SD/SDHC  
formatted cards.  The same card formatted in an M8/9 won't work, but  
will be read via the reader when formatted in the Lumix or Canon S90.   
The card tab is not in the lock position.

Might be that my Mac cannot read Leica formatted cards.  Absolutely no  
idea how to remedy this.  Anyway, my workaround is to USB link the Ms  
to the Mac when I upload image files.  And when I transfer a firmware  
upgrade file to the M9, I make sure the M9 is set to Mass Storage  
mode, so I can put the file to the card in camera from the Mac  
directly.  However, the M9 does not have Mass Storage as an option, so  
it needs a card reader to get the firmware file on it.

Now I am going to be careful and try putting an M8 card in the M9,  
then connect to the Mac via USB.  Then I will put the M9 firmware on  
the card.  Of course, I will not try to run the firmware on the M9!  I  
don't want a Silver Grey brick!  If I can get that firmware file on  
the card, then I will switch the card to the M8 and try to upgrade the  
firmware from there.

Fingers crossed!  I'll let you know if it works.

Peter