install ubuntu with pre-existing partition

p.s. i used windows disk management to creat partitions but it appears unusable when i tried to install ubuntu on tht

Did you try to boot from a live CD or did you only attempt to use the wubi installer?

What error message (if any) are you getting using the wubi installer?

Ubuntu should definitely be installed on an 'empty' partition. It can not be installed on a FAT or NTFS partition and thus attempting to do so will cause the installer to reformat the selected partition(s) with one of the EXT(2,3,4) or other linux-filesystems. (Reformatting means you lose your data)

In your case I would suggest installing Ubuntu to the 140G 'other' partition and leaving a couple of GBs as a swap area.

When Installing from a live CD you get an option on how to partition the harddrive during the installation. You should select one of the 'manual' options which will let you customize exactly where to install Ubuntu. The installer should recognize your Windows partition and warn you about any actions that would overwrite your data.

thx for ur reply
i hv tried both but no success

if using wubi the error: Invalid argument
for more information, pls refer to c:\user\user\appdata\local\wubi-10.04.1-rev190.log

there is problem on partitioning too. Whatever I free harddrive space by windows disk managing wizard or the disk managing function in the installation CD, the space I free always appears as unusable, ie I shrink the disk by these methods.

I've had considerable problems getting ubuntu installed on a win 7, vista, and xp systems myself. How I got it working was to set aside a free partition using Gparted on the USB stick.

I process I used is:
1) reclaim the free partition you created with disk manager in win7
2) insert your usb drive and run the trial version on ubuntu
3) resize the windows partition with gparted
4) reboot
5) install ubuntu from the usb stick, and when asked, install to the largest contiguous free partition

voila

hope this helps

thx very much
using GPART i creat a partition for ubuntu and it is successfully installed

however, i cannot boot from win7 ask it said BOOTMGR missing
how can i solve this?

http://www.howtogeek.com/howto/windows-vista/fixing-bootmgr-is-missing-error-while-trying-to-boot-windows-vista/
Tha should also work for win7 installations.

If you use a dedicated partition for Ubuntu, I advise you to forget Wubi, which will in this case provide any advantage and some drawbacks. Instead, use directly a dual boot with Ubuntu CD (Wubi was designed to avoid partitioning and it's only advantage, but it's dual boot mechanism is not perfectly reliable).
In this case, remove "Wubi" project from your question, and replace it by "Grub2". You will get more answers.