So I tried to do a fresh install of Mavericks - I erased my HD with disk utility and then went to "reinstall" by selecting the reinstall option. It asked me to sign in with my Apple ID to download OSX, but when I signed in it said my ID has never purchased Mavericks! so now i'm stuck! my iMac is wiped clean and I have no way to reinstall OSX. help! ---------- So I was able to login with my MacBook and download mavericks to that device. And now it's letting me download to my iMac. Odd. Resolved for now.