can't mount an untamed horse, it just neighs at me and doesn't allow any taming attempts (i.e. my player can't even sit on the horse to get thrown off). Have tried to feed it but this does not help.

http://minecraft.gamepedia.com/Horse#Taming

To tame a wild horse, approach it and right click on it with an empty hand. ...

this does not fix my problem, I've tamed and bred various horses before without problems. However, now i cannot even ATTEMPT to tame a horse. They literally just neigh at me and buck at the air. My player at no time mounts the horse nor is able to attempt taming. Like i said, I've tried feeding untamed horses, mounting various different untamed horses etc. I can also not attempt taming mules or donkeys. Taming with all other mobs works just fine.

I am having the same problem. I encountered this on my hardcore world. I found a pack of 3 horses, two adult and one foal. Right-clicking them does not lead to mounting it and instead it just neighs and kicks. continuously holding right-click on the horse leads to it continuously neighing and kicking. I have been able to successfully tame horses with my minecraft before. Playing 1.7.2.

Either you're not right-clicking them with an empty hand or the horses are not fully adults.

I'm also having the same problem. Is it because of the new updates? I'm not so sure and I need help!!

And I've been able to tame horses perfectly fine before as well

@unknown: MC-89924

So, this seems to be a strange bug with mouse controls, but (un)fortunatly i got it not just in one save, but in all my saves (1.12.2 forge) (maybe 107 mods has something to do with this) and so figured out some stuff:

1) Bug (in my case) works like this: i click on any rideable creature, camera swings in a random direction, but always stays exactly horisontal, and nothing else happens

2) If i press shift, it works fine some times, but i`m pressing shift, so no luck

3) The direction of camera movement is the same, until horse moves, then its other direction

4) [Solution]: rmb on a horse, position yourself, so when you click next time your cursor would stay on horse (the horse is a little bit below the 'cursor horison', so you must be one (or half (or fraction of)) block below, click again => profit.

5) The bug seems to happen, when you click on a horse and normally it would reset camera position after you embark, but it instead resets first, and then tries to check, what you clicked again (one time it opened a chest (mailbox, actually) after reseting the camera) and if it is not a horse, no luck then. Shift 'works' becouse it makes your 'cursor horison' a bit closer to the ground => closer to the horse (enough to hit)

6) [Better solution] By using a shovel on grass you make a pathway. A pathway makes you low enough to hit a horse, so does the soul sand (i think)

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