HI this is what the error message means
STOP 0x000000ED or UNMOUNTABLE_BOOT_VOLUME
Windows XPwas unable to gain access to the volume containing boot files. If you see this STOP message while attempting to upgrade a system to Windows XP, verify that you have compatible drivers for the disk controller and check the drive cabling to make sure it is configured properly. If your using ATA-66 or ATA-100 drivers, make sure you have an 80-connector cable, not a standard 40-connector IDE cable. Also works in with these next 2 as well. In some cases, this error will spontaneously correct itself after you restart your system. The one below works in with this one.
STOP 0x0000007B or INACCESSIBLE_BOOT_DEVICE
Windows XP was unable to locate the system partition or boot volume during the startup process. Thid problem may occurr after repartitioning disks, adding new disks, or upgrading a disk controller and its drivers. In that case, entries in the Boot.ini file no longer point to the correct partitions. If the error occurs after upgrading the disk controller, verify that the new hardware is configured properly. Then start your system with the Windows XP CD, log onto the Recovery Console, and use the Bootcfg command to scan for available Windows installations and repair the Boot.ini file automatically.
STOP 0xc000021a or STATUS_SYSTEM_PROCESS_TERMINATED
This message indicates a serious security problem with Windows XP - a user-mode sub-system, such as Winlogon or Client Server Runtime Subsystem (Csrss.exe,) is compromised. The most common cause of this program is a third-party program, and the solution is usually to remove that program. This error can also occur if a backup set has been partially restored, causing a mismatch in system files, or if system permission have been incorrectly modified so that System account no longer has permission to access system files and folders.
Hope this helps you.
Edited by thedon57, 17 August 2005 - 10:02 AM.