Friends If you have been installing ubuntu in your system at first then you have to install Windows XP or Vista after installed ubuntu.You can’t go with ubuntu because of,
First upon you have installed ubuntu so that GRUB written in your MBR(master boot record).then you have installed Windows XP..it overwrites the Linux boot record(GRUB).so that windows boot record is overwritten along the Grub.
SO,you have to replace the linux boot record over windows boot record..it is possible…
1.Boot your system using ubuntu live CD.
2.you have to open your terminal via live CD of Ubuntu
3.Type the following
(hd0,4) //This is nothing but the location which have the ubuntu
Grub successfully installed….then you can reboot your system…you can view ubuntu as well as windows
| |———–>you have installed Ubuntu in 5th drive of your hdd..
|—————> primary master hdd