Don’t confuse bootsec.exe with bootsect.exe, as they are different files with different functions.
BOOTSEC – Reads the Boot Sector of a drive: http://support.microsoft.com/kb/102870
BOOTSECT – Tool for rewriting the Boot Sector of a drive partition. This tool is found in Vista and Win 7, and can be used for those OS as well as Win XP (with the /nt52 switch)
http://technet.microsoft.com/en-us/library/cc749177(WS.10).aspx