pls help: I can't start my mac because I took too much space and now the disk doesn't mount

Use one of the following to analize what's taking up disk space:

OmniDiskSweeper

GrandPerspective

WhatSize

Disk Inventory

I am curious. What happens if you start up in target disc mode, do you get that far? And if so, do you have another machine there you could use to hook up?

Here's my opinion. If you're not familiar with the command line interface—and you don't seem to be—then you run the risk of doing serious damage and wasting your time. It's one thing to give you exact commands and paths to use, and quite another to remote-guide you to find files to delete.

So my suggestion is, first, try to boot in Safe Mode. In this mode, some caches are deleted automatically, so maybe the machine can start up this way.

If it doesn't work, then get an external device. You need one anyway—this incident should have taught you that having backups is not a luxury, but a necessity. (If not a external drive, then a 16GB or 32GB thumb drive or SD card should do.) Boot from the install DVD, install a minimal system on the external device, then boot from the external device and do any housekeeping on the internal drive you need. Once everything is back in working order, don't forget—you should always have with you, even when you travel with your MBP, (1) a full, working, current backup, and, (2) an emergency boot device. After this exercise, you'll have at least one of them.

Boot in safe mode, by holding shift as soon as you hear the startup chime then a little progressing bar should appear if you've done it right, see:

http://support.apple.com/kb/HT1455?viewlocale=en_US&locale=en_US

Then get an external HDD (hard disk drive) and connect it and back it up, then delete files off your mac that you do not need, or you can use the HDD for a start up drive so you can start it up, use disk utility then reformat the HDD to "Mac os x (journaled)" So open up disk utility>make sure your external HDD is connected, click on that>then click partition at the top>then choose how many partitions you want (in partition layout)>then click options>then click "GUID partition table"

Then once thats completed, shut down your computer, then start up but straight after the chime hold the "alt" key to select which disk. Then select your external HDD to start up. Then move all your files to that external HDD.

Or there is a simpler way,

Just buy an internal HDD then open up the back put the back of the computer (chassis) face down so the inside of it that you never see, you can see, rest your arm on that to discharge you of any static, then disconnect your HDD & then recconect your new one. Seems hard, but it is very easy. Google "Change internal HDD mac" and look at some articles and vids;)

Vids are easier to follow.

Any more help needed just ask;)

Ciao

adamfromcernosice wrote:

I should Install OS X on an external flashdrive

Yes.

is 16gb enough?

Yes, it should be.

is there any specefic one that I should get?

Any good one should do. SanDisk… Kingston…

How do I proceed with the instal?

1. Power off the MBP.
2. Connect the thumb drive.
3. Insert the Install DVD.
4. Power on the MBP while holding down the C key. The MBP should boot from the Install DVD.
5. Go ahead with the installation, up to the point where you are asked to select the target volume.
6. At that point, choose "Disk Utility" from the Utilities menu.
7. In Disk Utility, select the thumb drive (the drive, not a volume on the drive).
8. Click the Partition tab.
9. In Volume Scheme, choose 1 partition.
10. Click the Options button.
11. Choose GUID Partition Table, click OK.
12. In Volume Information, enter a simple name (eg, SOSdisk).
13. In Format, choose Mac OS Extended (Journaled). Leave Size alone.
14. Click Apply. Once it's done, quit Disk Utility.
15. You'll return to the installer's volume selection screen. SOSdisk should now appear as a choice. Choose it.
16. Click Customize.
17. In the Customize screen, de-select everything, then select Rosetta (which is de-selected by default). Confirm.
18. Follow on-screen instructions to complete the installation.
19. When the installation is complete and you re-boot the machine, hold down the Option (⌥) key. This should bring up the EFI boot options.
20. Choose the thumb drive. If everything went well, the MBP should boot from the thumb drive. It will be significantly slower than running from the internal drive, but not quite as slow as running from the optical drive.

After you've attended to the emergency, you can add to the thumb drive utilities which you might need in an emergency. A disk usage tool (eg, OmniDiskSweeper), a hex editor (eg, 0xED), a text editor (eg, TextWrangler), a burn tool (eg, Burn), a cloner (eg, Carbon Copy Cloner) and a sync tool (eg, SyncMe2), search tools (FindAnyFile, EasyFind, Find File), a command line database (CLIX), a few odds and ends (eg, Onyx, AJA Systems Test). Also, some references (eg, a Unix tutorial and guide to basic commands) might come in handy.

adamfromcernosice wrote:

I could not delete anything - it always showed "error code -50"

That error is rather generic ('error in user parameter list'). I don't know what's causing it; but, under the circumstances, it's quite possible that the file system on the internal drive is corrupt or the directory is damaged. IMHO, the cleanest solution would be to re-format the drive and restore everything from backup, but that option is not available to you.

The next best would be to run Disk Utility and check the internal drive (verify disk, not verify permissions!) and repair, if possible.

If DU doesn't find anything wrong, or can't repair the drive, you can try deleting items in Terminal. In a Terminal window, at the prompt, type

rm -r

(there's a blank space after -r), then drag the item you want to delete from Finder to the Terminal window. Its path should be entered on the command line. Make sure it's the right item—there's no undo! Once you are sure, hit the Return (↩) key to execute the command.

If rm throws an error, you may try using it with the -f option

rm -fr

The nuclear option is using rm as root (superuser), which allows you to delete absolutely anything, and thus completely destroy your system, if you're not careful.

sudo rm -r

You'll have to enter your password (which will not be echoed to the terminal), then the command will be executed.

You must use Disk Utility to verify and repair the disk after you've cleared up some space. DU may not be able to fix it, in which case you can shell out the moolah for DiskWarrior (which may or may not be able to fix it), or back up all you can, then re-format the drive (which, of course, will destroy all data currently on the drive). As I said earlier, I prefer the latter option.

adamfromcernosice wrote:

| just read that the password doesnt show while being typed - ok, but still it says "invalid argument" once being typed after the sudo rm -r. how is that possible?

Probably some error in typing. Copy the command line from Terminal and post it here, exactly as it is.

a way to install applejack or someother helpful software?

AppleJack only works on the boot disk, and only in single-user mode. IMHO, if there is a space or corruption issue on the disk, the last thing you want to do is to install new software on it.

DU once I select repair disk reports ''it could not unmount'' the disk.

If you chose the right disk, you probably have some process using files on the disk or referencing the disk. For instance, if you have Terminal open and present working directory is on the disk, DU will refuse to unmount it. Make sure you've quit all other apps before using DU. If it still refuses to unmount, you can force it in Terminal

$ diskutil unmountDisk force

and drag the disk from Finder to the Terminal window (there's a blank space after force).

could I somehow use time machine just for my original disk?

I don't know about Time Machine. I suspect you can't use it under your circumstances, but I really don't know.

how to force through adn delete some folders? I still believe that it should solve the problem, shouldnt it?

Not all problems have convenient solutions. If the file system is corrupt (which could well happen when running out of space, let alone the fact that you couldn't boot from the disk and thus the journal couldn't be replayed), then deleting files may not work or may make matters worse. We still don't know why you couldn't boot from the internal disk. It may be because there isn't enough space to create the necessary temp and ancillary files—or it may be because the file system was badly corrupted when the operating system ran out of space.

If you want to stick with it, post here the rm command, as I wrote above. It may or may not work, it may or may not delete the files you want to delete, which may or may not fix the problem. There's no guarantee. It you want to do it right, the only way is to back up everything you can and re-format the internal drive.