To ask what do you do when your husband is in a terrible mood?

[Waterbottle1999]

My DH's computer broke, he had built it himself and was so upset when it died. He's been walking around the house dejected all day and nothing I can say or do helps so, what do you do when your OH is right down in the dumps?

Let him work through it. Maybe a beer and a takeaway at the end of the day.

Where has OP said her DH is sulking or acting like a child?
Yet people are referring to those things as if they're fact!
The only thing OP said is "upset", "dejected all day" and "down in the dumps".
Doesn't seem unreasonable if a valued possession is lost.
(Apart from downcasteyes who thinks everyone should be exactly like her).

I'd cook his favourite meal and lots of hugs.

Nothing, he goes into our study, retreats into the cave (like in Men Are From Mars...) works it out and comes out ok.

I'm more of a stampy round the house oh for fucks fuckity fucking saking for a few minutes then I'm done!

The OP hasn't said he's sulking. She says he's upset.
Where has she said he is acting like a child?

All I read in the OP is that she knows he's upset and she sympathises and wants some ideas for how to help him feel better.

OP what works if DH is stressed or upset is to give him one hug to let him know I'm there and on his side, make him a cup of tea and let him get over it for himself. He doesn't like a lot of fuss but when he comes out of it he always says thank you for the hug and the tea, and that they helped.