How can I get My chihuahua to go for walks on a leash?

OPERATING THETAN LVL 5 (tara): My chihuahua won't walk on a leash, what can I do to get him to go for walks?
He's 2 yrs old and neutered and is absolutely terrified of the leash. He immediately lays down and will not move when I put the leash on him. I feel bad because he acts so depressed when I take the leash off he mopes around for hours. I have tried everything, even enticing him with treats and food, leaving the leash on him inside to try to get him used to it, and walking him with the rest of my pack. I have taken him with my girls (1 yr old Affenpinscher & 14 yr old Sheltie mix) who just love to walk, and I always end up carrying him. He acts so pathetic, I have never seen a dog act like this- he literally freezes, lays down and will not move until the leash comes off. I don't want to drag him cause I know its not good for little dogs, plus he yelps even with the slightest tug on the leash, I don't want neighbors to think I'm abusing my dog. If anyone has experience with a little dog that won't walk or had a similar problem, all feedback and suggestions are greatly appreciated! Thanks!
I guess I forgot to add in that he is NOT wearing a regular collar he has a step-in harness and has been in one for awhile now.
I use a lightweight leash that is pretty short, I bought all 3 of my dogs these leashes (and they all wear step-in harnesses, I already know regular collars can cause trachea collapse in small dogs) since I have 3 toy/small breeds. I have tried to get him to go outside without the leash but he seems to be just as scared of going outside without it. I also carried him a few times on walks with my other 2, hoping that he might see my girls walking and want to join in the pack, or just get used to the idea of being out of the house/backyard area, but hes just scared. I think this is probably my fault because I babied him so much when he was a puppy, the first time I tried walking him he did this and I just let it go cause I felt so bad trying to force him to walk. When I got my Affenpinscher (also a toy breed if youre not familiar with them) as a pup, she took to the leash right away and I had no problems with her.

Answers and Views:

Answer by Me-ow
Start walking him on a leash in the house,thats how I started mine

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