Hi, am having problems with my two Dell Optiplex mashines. One had viruses, i cleaned and the other one was not working properly which i decided to format the mashine and reinstall windows. During installation it was freezing so i thought the hard disk (SEAGATE sata) had some problems, i decided to remove the hard disk without shuting down the mashine, then i took another hard disk (SEAGATE sata) from same model optiplex which i was scanning. This HDD was connected throught IDE to SATA device externally on another mashine. After i connected the HDD to this mashine which was on, i restarted the computer then i gave me the NTLDR is missing error while trying to boot. I thought the disk is corrupted but amazing while connected the other HDD gave me same error. I changed the mashines but still can boot, even i took another new HDD sata same SEAGATE but can not work on these two mashines same error! What to do or what can be the course of problem? Please help! Makota.