Macintosh HD icon is not on my Desktop or visible from the Finder

This is a strange one.
I'd first try running +Disk Utility+ and repair permissions.
Run it a few times until no errors appear. Ignore the ACL warnings if they happen to show up.
Reboot and see if your Finder is back.

If that doesn't work, I'd make a backup of your drive for safe keeping then I'd boot off the OS X Install DVD and run +Disk Utility+ again.
This time tell it to check the drive for errors. If some appear I'd go ahead and do a repair. This is where the backup might come in handy just in case +Disk Utility+ can't fix the drive.

Reboot and see once if everything was back to normal.

If not... sigh ... I think I'd do a reinstall of the OS.

Good luck!

Oh, Happy Day!! I think I have a fix!!

First a disclaimer. I didn't come up with this fix. I can not take credit for this. If this works for you, send your "kudos" to Daryl the Genius Bar dude.

You see, my MBP has been having a disfunctional battery ever since I installed a firmware update. And that was right before I updated OS X from 10.4.10 to 10.5.0. I tried everything to get that battery to hold a charge longer then 1 hour. Yesterday I gave up and stopped in at the UTC Apple Store where I was luckily helped by a Geniuses named Daryl.

The battery problem was solved by a swap out (thank you AppleCare). Then Daryl asked if there was anything else, and I said "Yea sure, but there is no way you'll be able to fix it. No one has figured this one out".

A challenge had been issued and Daryl attacked it head on.

To cut to the chase and after about 15 minutes (Daryl was multi-tasking and working on another Mac otherwise the time would have been only 10 minutes) he came up with what I now think is a fix.

He discovered that the +Group ID+ on ~/Library/Preferences/ByHost was incorrect. It had me as the owner, but the group was a carry over from the 10.4 days.

Running the following from my Preferences directory
+sudo chown paul:staff ByHost+
set the owner and group correctly

You should also make sure the permissions on that directory are set correctly too.
+sudo chmod 751 ByHost+

Once I rest the "V" bit on my root drive and rebooted everything was working fine. Including some strange issues I had with iTunes not storing any preference changes. ...Turns out iTunes stores some preferences in the ByHost directory.

For over 12 hours, my +Macintosh HD+ has been sitting happily on my Desktop and in my Finder. I have even issued a command to force Spotlight to reindex my hard drive. Normally, that would reset that ole "v" bit. But this time it didn't!

I'd love to hear if this fix works for you.

Oh Happy Day!

Oh never mind!

The Missing Hard Drive problem is back and ByHost still has the proper user:group ID. The drive disappeared after I did a reboot just now. Sorry for the false alarm folks.

Nothing new. The folks at Apple did ask if the dialog box in TextEdit was able to see the missing hard drive. On my machine, neither the Open or Save (As) dialog boxes see the drive when the "V" flag is set.

So, they are working on it but so far nothing solid in the way of a fix.

Rich,

When you say you have a "segmented drive", I presume that at one time you partitioned your drive into two volumes: Macintosh HD and Audio. I have a similar configuration: Macintosh HD and Le0. The Le0 volume I use to run (oh, I'm going to get flack for this....) Vista on Parallels.

The partition should not have any impact on either performance, the disappearing drive or Time Machine failing to back up your Mac HD.

What I would do is the following:

Startup +Disk Utility+ from your Utilities folder.
Select your +Macintosh HD+.

Take a look at the amount of Available space you have. 10.5 seems to have a greater memory footprint and at least on my laptop needs to swap even with 3GB of RAM. If your Mac HD doesn't have enough space, your machine will be sluggish and that might even explain why Time Machine won't back up your root volume. The Audio volume could be backed up because it has enough Time Machine scratch space to keep TM happy. This is all speculation so value my view as much as I value the OS on my Le0 partition.

If you don't have enough room (some say 5 - 10% of the volume size as a minimum, I say 3 - 4x RAM size) then you have some house cleaning to do. I have removed log files to make room. Sometimes (though luckily rarely) a log file will get a bit out of control. If you need help with removing these files let us know or search the Discussion lists.

Finally,
Select +Repair Disk Permissions+ to fix those permissions on your root volume +Macintosh HD+


Repeat this until +Repair Disk Permissions+ doesn't find anything that needs a fix'n.
Note - +On my machine Disk Utility says that the repair will take 1 minute. Evidently, Disk Utility is moving close to the speed of light while I am at rest, because I swear a good 4 minutes goes by in my temporal frame of reference.+

In the unlikely event (though I had this problem) you Disk Utility keeps giving you a message about permissions, record what it is finding and report back here. Mine kept giving me ACL permission messages. They should be harmless, but could be an issue.

Reboot and see if your machine is running any better.

If it is still sluggish, launch +Activity Monitor+
Select Window and then +Activity Monitor+
Look for any processes that are running close to or greater then 100%.
Record the name of those processes too and then report back here.

Good luck.

I don't believe it has anything to do with partitioning. I have another Mac (iMac G5) that has only one drive with only one partition. When that machine was upgraded to Leopard, the disappearing root drive fungus attacked.