My laptop was dual booting Windows XP and Ubuntu 10.04.
Recently I completely formatted my 250 GB HDD and installed Windows XP in a 5GB partition. Then installed Ubuntu 12.04 in remaining space. But WiFi is found to be slow in 12.04, so I decided to revert back to 10.04.
I removed the Ubuntu partition from Windows and tried to install 10.04. But after 44% it shows an error message that
Copying is not possible.... I thought it may be the problem of installation disk. So again tried to install 10.04 from a USB. But it also shows the same error.
When I restarted, it shows booting error that GRUB was not found. As I am not an expert in Ubuntu, I tried to re-install Windows XP. Then it shows the error
cannot format disk. So now I am not able to install Ubuntu 10.04 nor Windows XP in my laptop. Then I again tried to install 12.04 and it worked.
How can I revert this 12.04 to 10.04 and install Windows XP?