I have a craftsman 17.5 horse riding mower, it was working and I parked it for about a week and now it won't start, the battery if fine.. I replaced the solenoid because there was no power going to the starter. Same preblem with the new one, if I jump the solenoid it will turn over.

Hi,
I gather that you are jumping across the large terminals, which tells you the battery is good. Try jumping from the battery side to the small terminal (if there is only one) or the one with the red wire (if there are two.) That checks the solenoid if it has only three terminals total.
Peace,
Clarke