I have a rebuilt desktop computer that has a Maxtor HD and a secondary HD that I installed in it immediately after purchase. It has been running fine ever since I purchased it. Although I have internet on it, the primary function of this computer is to store information off my surveillance my cameras around my home. Although the cameras don't run 24/7, I do not shut the computer off and it is on continuously. When I walked in last night to review the footage of that day, I was greeted with the "Disk Boot Failure, Insert System Disk and Press Enter" message. Needless to say I was shocked by the message and even more surprised when I realized that I didn't have the boot disk cd. Nothing has been installed or taken off since the first installation. The internet is on only when someone powers up the hot spot wireless device. As I am the only one that has access to the computer, I can imagine it having a virus because I don't surf on it. Very seldom do I use the internet. My OS is Vista and the Maxtor is a 40GB HD while the secondary is 80GB HD. Could anyone tell me how to fix this problem?