Low spark can't start been setting 3 yrs.

clean carbs and replace spark plugs

No adjustment for carb on newer mowers. All mowers now have a low oil cutoff. Ensure oil is full. 30w oil. If any grey is observed vin oil drain all oil. Moisture in oil. Dump old oil out every 2 yrs and refill. Ensure spark pluf is clean and gapped correctly. Ensure air filter is clean. Replace spark plug and air filter each year. Always use Stabile in gas. Spray outside of carb with carb cleaner to ensure proper choke movement.

Electronic ignition units work off speed of rotation so make sure yoy are cranking the engine fast enough, make sure the plug is well earthed against the cylinder whilst cranking, make sure the switch is in the on position, if there is still no spark you will have to replace the unit.

Try a little starting fluid in the intake (not too much, just enough to test). If it takes off for a second or so, may be water in gas. Ten months old? It should be alright, unless it's loaded with water.

Igniter usually. You need a few things. Do you have fuel? To the carb not just in the fuel tank. And do you have spark? Check all plugs. Turn car over with a plug wire removed and see if you have spark otherwise you need to diagnose air intake or compression. Usually igniter if you have no spark.
Hope this helps.

try running it with the gas cap loose the vent might be plugged

test battery -is it holding 12.6v charge-if not then its over 3 yrs old or the alternator is bad--also inspect inside distributer cap and plug wires--they get corroded and need replacin

This could be a few different things. 1. Check oil level, if your machine is equipped with a low oil sensor the engine will not start if oil is low. 2. Check the spark plug, remove it and place it against something metal and crank the engine over while looking at the spark plug to see if you have spark. Don't hold the plug because you will get a shock. 3. Check the carburetor, remove and clean. Check the air filter, make sure its clean. If these steps don't work let me know.

If it was me, I'd take the time first to remove all spark plugs and add enough diesel fuel to cylinders through spark plug holes to at least cover top off piston well, and let it sit and drain down through rings etc. Do this numerous times over a few days, or even week if you have the time, and see if it will un-seize any possible seized rings. Have done this on a nice little Chevy II years ago and saved a seized engine.
Smoked for approx 10 minutes on first start after sitting for 3 yrs. and then purred like a kitten from then on. Be sure to drain oil from crankcase which will be where the diesel fuel goes as it seeps through rings. It's worth a try, and would be a low cost fix if it works.

Has it got a low oil sensor? Most hondas have Try putting some more oil in motor