Roasted chickpeas for houmous? I accidentally bought roasted, salted chickpeas (I've never heard of this - why would anyone want that?) instead of normal, dried chickpeas. To be clear, these chickpeas are dry and powdery, rather than boiled chickpeas roasted with salt to make a soft/crispy snack.

Can I still use them to make houmous? Or should I give this one up?
Roasted, salted dry chickpeas are a snack food.  

I would not expect for you to be able to make humus out of them; for one thing, they would have way too much salt, and the texture would be wrong.  It might be possible with a lot of experimentation, but you'd need to go through several failed batches before you got one which worked.  Personally, I'd just go back to the store.