ubuntu 9.04 installation problem

[Mahadi Hasan]

I've recently recieved a CD of ubuntu 9.04 that I requested.
I tried to install this version replacing the 8.10 one with Window xp
in another partition, but I failed.
I completed the preinstallation processes, and when I finally clicked
on the install button a dialoug box showed up, and after 15% of the
installation process it went back to the partition table. It happened
over and over again I tried. I had used ext4 filesystem with mounting
point / and location in the partition is Beginning for both ext4 and
swap space, and I had used manual partition method.
My pc specs:
Intel celeron D
RAM 512
HDD 80 GB

Help me.


Regardin,
Mahadi Hasan