I stealth a far bit so I was fighting a boss....got lucky killed him and found I could not get my character out of the crouch/stealth position.

I fast traveled and ended up in crouch.I went to an earlier version of the game an am still in a crouch.

I am using mods..... SKYRE being the principal one.

Can any suggest any solutions ?

Could I have a corrupt file ?

This is a game ending problem ,so I hope there is a solution.

Thanks.

Try sitting down on a bench or chair, or use a forge, grindstone or something that forces the character out of the crouching animation. (Not sleeping obviously, since you don't see your character sleep). I always do this when mine gets stuck and it works for me

...and no, it's probably not because of mods.

I don't have any mods and I crouch and stand just fine.

So one of your mods is conflicting with another mod, I say.

Depending on how many mods you have, ALWAYS read the description of the chosen one.

Sometimes that doesn't help, it's a gamble.

It is caused by loading a save where your character is in sneak mode.

it's easy to fix. Just interact with something like a chair, forge, alchemy lab and stuff like that.

Explains it, had it before, more weird Serana was locked in knockdown position once, luckily an load door solved the problem.