I created a USB to install ubuntu 10.10 on an IBM ThinkPad T42 but when I reach the "Preparing to Install Ubuntu" screen it gets stuck there whith the mouse as a wheel

make sure you have at least 15 gigs of free space on your hard drive. you might have to defrag your hard drive first

I have 30 Gigs of free space

Do you install inside Windows partition ?
@Marcus: why defrag hard disk ? You can only defrag a partition (and a Window's one).

I currently dont have Windows installed its a blank Hard Drive that I want to Install Ubuntu on But
for some reason the installer gets stuck on "Preparing to Install Ubuntu

@delance
thinkpads come with windoze installed and if it's installed, he'd need to defrag it as windoze files are often fragment. with only 30 gigs hard drive, he might have 15 gigs available, but it would be scattered all over the harddrive and not contiguous, so he won't be able to install ubuntu.

@oscar
stealing from actionparsnip

1. did you do an md5sum check on the iso file after downloading it?
2. did it burn it as slowly as possible onto a cd rom?
3. did you check for defects on the burned cd rom?

@Marcus
You are right. As I stopped using Windows, I sometimes forget some such stupid issue.

Windows is Not installed on it it has a blank Hard Drive that has 30 Gigs and defraged

Stealing from both marcus and actionparsnip:
   https://help.ubuntu.com/community/HowToMD5SUM
If checksum is OK, we can search a hardware issue.
Please, boot on CD, choose "Try without install" and then System->Administration->Test System
Could you also provide partition table.
In a terminal (Applications->Accessories->Terminal), type the following command:
    sudo parted -l
where "-l" is lowercase "L". This will display list of partition.

I did it my computer is fine and ubuntu still wont install

Please, boot on CD, choose "Try without install" and then System->Administration->Test System
Could you also provide partition table.
In a terminal (Applications->Accessories->Terminal), type the following command:
    sudo parted -l
where "-l" is lowercase "L". This will display list of partition.

Do i have to boot on CDor from my usb

As you want.

Hey! I have the same issue and have also tried the following things:
- check md5sum
- install 10.04
- install from USB or CD
- try a different PC

For the above mentioned command
sudo parted -l
I get the message: You have found a bug!
The verbose message can be found further down...

This was with parted version 2.2
Tonight I will try to update the persistent ubuntu system on the USB-device and update parted, too.

- - - - - -
Model: ATA WDC WD1200JB-00G (scsi)
Disk /dev/sda: 120GB
Sector size (logical/physical): 512B/512B Partition Table: msdos

Number Start End Size Type File system Flags
 1 32.3kB 120GB 120GB primary ntfs boot

Backtrace has 16 calls on stack:
  16: /lib/libparted.so.0(ped_assert+0x2a) [0xed3f0a]
  15: /lib/libparted.so.0(+0x42507) [0xf0b507]
  14: /lib/libparted.so.0(+0x43317) [0xf0c317]
  13: /lib/libparted.so.0(+0x4460c) [0xf0d60c]
  12: /lib/libparted.so.0(+0xf7b1) [0xed87b1]
  11: /lib/libparted.so.0(ped_disk_add_partition+0x262) [0xedc032]
  10: /lib/libparted.so.0(+0x45fa3) [0xf0efa3]
  9: /lib/libparted.so.0(+0x4619f) [0xf0f19f]
  8: /lib/libparted.so.0(ped_disk_new+0x75) [0xedce15]
  7: parted() [0x804e389]
  6: parted() [0x804f553]
  5: parted() [0x80517da]
  4: parted() [0x8052e51]
  3: parted(main+0x2e) [0x8052f5e]
  2: /lib/tls/i686/cmov/libc.so.6(__libc_start_main+0xe6) [0x312bd6]
  1: parted() [0x804c3f1]

[ ...... ]

and the following history of commands you entered.
Also include any additional information about your setup you consider important.

Assertion (head_size <= 63) at ../../../libparted/labels/dos.c:659 in function
probe_partition_for_geom() failed.

Aborted (core dumped)

- - - - - -

I did not succeed in updating parted.
But I managed to install Ubuntu from CD!

There seems to be a problem with parted and USB devices.
My error was, that I left the USB device stuck into the computer when installing from CD.
So parted checked the USB and crashed.
Without the USB device the installation from CD works fine!

The installation comes in many steps, and all steps don't enumerate mass memory storage in same order. So sometimes, they don't communicates data properly between them, specially with USB key or internal flash memory.