I had the same problem. Here's what I did. I would turn my key and nothing happened. Before you do anything. Make sure the blade is not engaged as your mower will not turn over if it's engaged. Afterwards (if nothing happens) take a screwdriver and touch the positive and negative posts on your solinoid (do not have anything flammable on your hands) Make sure the key is on and when you touch the posts the motor should turn over and crank up. If not the solonoid may be bad and you would need to get another one. Costs about $12.00. Let me know what happens. Mine runs fine now after replacing the solonoid.

I had the exact same problem. Here's what I did. I would turn my key and nothing happened. Before you do anything. Make sure the blade is not engaged as your mower will not turn over if it's engaged. Afterwards (if nothing happens) take a screwdriver and touch the positive and negative posts on your solinoid (do not have anything flammable on your hands) Make sure the key is on and when you touch the posts the motor should turn over and crank up. If not the solonoid may be bad and you would need to get another one. Costs about $12.00. Let me know what happens. Mine runs fine now after replacing the solonoid.
Those are not positive and negative post on the solenoid tom, they are both positive, one being the feed line, and the other being the fed line. FEED AND FED.