I recently backed up computer for the first time using Microsoft installed backup function installed with xp. Backed up to external hard drive. I restarted the computer and now I have missing NTLDR. I tried to repair using the recovery disk I got with the computer. Problem is the computer is now looking at my external as the c: drive. How do I get the computer to recognize my c:drive as the internal rather than the external? I did the diagnostics on the internal HDD and it checked out ok.