MunsterBacca

Are you using steam? if so, in the settings for KSP are you opted into the "beta program" for 1.7? Assuming yes, opt out. You will be up to date and should be able to play. *should* That was my solution anyway, after using older versions for mod support, i assumed 1.7 was up to date enough to be compatible. Nope, needs 1.7.1.****