What do I do now? I have a wiped-drive disk and nothing to start it again. Invalid system disk.

USAFRet

Titan
Moderator
Then you need to reinstall the OS.

Do you have a valid activation key?
Assuming we're talking about Windows 7, you can download the relevant ISO here:
http://www.w7forums.com/threads/official-windows-7-sp1-iso-image-downloads.12325/

Burn to DVD, and isntall