NEED HELP LEXMARK PRINTER INSTALLATION MS DOS?

Yes i just received a new tower from my grandmother yesterday and trying to print out shipping labels for my items well i dont have the disc anymore i went to lexmark website to download it well says c:\windows\systems32\autoexec.nt. the system file is not suitable for running ms-dos and microsoft windows applications. choose 'close' to terminate the application?!?!?!?!??! what should i do now? what do i need to change or correct please help anyone.. tech suport keeps getting disconnected from me?? im lost thanks!