LA130 won't start

hi I'm hoping someone can help me. I had another person drop the deck to change blades for me and now the mower won't start. I'm wondering if there is a safety switch on the deck that prevents it from starting. I will be checking the battery tomorrow since I bought the mower used and have no idea how old it is. Thanks for any help.

Nothing on the deck.
Some JD's have a brake switch under the foot board but you should not have touched it when dropping the deck.
Is the brake pushed on hard and the PTO turned off.

Won't start does not tell us anything we can use
Cranks but does not start = one set of problems
Dose not crank = another
Cranks a little & stops = yet another.

Sorry I should have given a few more details. PTO off and break on hard. Does not crank at all. I know it could be the battery since I don't know its age but didn't want to go buy one if I was missing an obvious solution. I do know the previous owner somehow bypassed the switch so that you can back up without needing to change key position. (Hope that makes sense). Prior to having the deck dropped there didn't seem to be a problem starting. It usually wouldn't start the first time you turned the key but always on the second try. If you need other details let me know. Thanks.

When you turn the key to the on position you should hear a faint click, which is the carb solenoid opening.
If not then locate the fuse which is usually on the right side of the mower behind the dash / turret driver rtation, whatever you want to call the bit that the steering wheel pokes out of.
It is a std auto blade fuse.
Replace it, even if it looks good ( use a spare from your car ).
IF the engine still does not crank then locate the solenoid , it should look like this http://jdpc.deere.com/jdpc/servlet/com.deere.u90490.partscatalog.view.servlets.HomePageServlet_Alt
the bolt on terminal have wires that go to the battery and to the starter.
The one that comes from the battery should also have a thin wire coming off it ( the fuse will be connected to that wire ).
Jump that wire to one of the push on terminals near the bottom, Jump the other to ground. Polarity is not important either wire will do .
That should cause the solenoid to activate and the engine to turn .
If that does not happen then jump directly from the battery - to a good ground near the starter and the battery + to the + wire on the starter.
You will get a big loud spark if the battery is good and the engine should turn.

Thanks for the suggestions I will give them a try when it is daylight again.