Dual Boot HAD a dual boot system. reloaded OS1-Cdrive and now it won't dual boot--------OS2 is D drive. How can I get dual boot option at startup again?

SOURCE: dual booting

Boot to Vista. Then

• right-click "my computer", then "properties".
• click the "Advanced" section (Vista: on the left side bar).
• In the section that says "Startup and Recovery", click "settings".
• Under "Default operating system", choose "Windows Vista".
• REMOVE the checks next to "Time to display list of..." and "Time to display recovery options..."
• click ok to everything.

• Go to "Start", "Control Panel"
• Open "Administrative Tools"
• next, open "Computer Management".
• On the left, there's a side bar. Under "Storage", click "Disk Management".

• Now, If windows XP is on drive C:\,
  right click C:\ and select "Format"
• Click "OK".

SOURCE: Dual Boot XP 32 and XP 64 on different PHYSICAL drives on same PC

So you want to merge those to make it as dual boot system on one harddrive, right? Try these steps:

1. Go to start, control panel
2. Performance and Maintenance
3. Administrative Tools
4. Computer Management -> expand storage, click Disk Management
5. Right Click the drive containing XP32 that you want to use, click format... Choose NTFS then make it as Extended Partition.
6. Reboot your computer and try to see by Pressing F8 if there's an option of what operating system you are going to use.

*Drop me a comment if that works or not so I can assist you further.

SOURCE: i have windows vista home premium on sony vaio

Here is a step by step guide of how to dual boot.

http://apcmag.com/how_to_dual_boot_vista_and_xp_with_vista_installed_first__the_stepbystep_guide.htm

SOURCE: Dual Boot Ubuntu

1st, install windows or if you have already its good .

Then, download Linux distribution that suits You better
Download It and burn into a CD or DVD with ISO file you can use Magic ISO or other manufacturer

then Go to BIOS setup and set 1st priority is the CD or DVD drive and save and exit

and install follow the instruction of linux.

also if you chose capacity of windows or linux is to little dont worry you can make install a partition magic and resize what you like....

PS:
pls rate me if my solution solve the issue and you need more further information. but if is invaluable solution rate me fixya.

SOURCE: I need to setup a dual boot computer. I have 2

Do you have both operating systems installed seperatly ? In case of installing another operating system while one is present, the computer would've known to select the one of it by itself or through some menus while startup. If you have installed both operating system seperately than you may need to find out first that both operating system are able to boot with some menu choice from the startup. To dual boot computer one system has to set as primary while other as extended partition using some Harddisk utility like FDISK. If you need to reset the partitions make sure that both systems works together as dual boot. Win XP, Win98 works as dual boot, WINXP , LINUX works together , but WIX 95 and WIN 98 may not work for dual boot systems.