Late last night, while testing what I thought was my external hard drive, I accidently formatted my C drive. I did not realize this drive is the same make and size as the external hard drive that I use to make Acronis backups. I have been up all night trying to restore my C drive from the full Acronis backup. I have successfully copied the partition including the Windows XP Pro operating system from the external drive to the C drive - although I was having problems with the drive letter changing behind my back. This was finally solved by a Dell support technician in the wee hours - it was caused by interference from something else connected to the system while I was tinkering. In any case, after the restoration is completed, the system does not boot - an error message comes up like "Cannot access disk - check hardware" I downloaded the Master Boot Record iso file, burned it onto a CD using the "data" setting on my Dell Sonic Record software, and tried to boot off it to no avail. In addition, the drive letter may have changed again, although nothing was connected to the system except for the backup "D' drive. I am getting increasingly anxious about this because I use this computer in my business. Any suggestions would be appreciated - even if only to reclaim my data files.