Dogs with poor social skills oftentimes just don’t know better. They will bounce off of everything, jump on everyone, run around like crazy, and investigate everything they can get their paws, snout, and eyes on! These dogs can come from any background, whether a rescue or puppy from a great breeder; if they haven’t had experience in new places and new situations, this can be how they respond.
Determining if this is your dog is a little more complicated, but it is often seen when your dog isn’t very excited (or that there isn’t much of a reason to be excited). This is more than likely to happen when you are in their way or have something that they want. They will usually jump on you and try to push you back more than just jumping up to give you kisses. Often times they will jump on you and try to hold on when you push them away or try to move into them. Sometimes moving into them may elicit a growl because they want to back you off.
A relatively new invention that will definitely solve this problem is the no jump harness. It works by restricting the movement of the dog’s hind legs so that it can’t jump at all. This should not be a permanent solution but rather something that can be effectively used during training. It should not only stop them from jumping chain link fences, but also from jumping on people and furniture.
You shouldn’t stop this type of jumping. You need to diagnose your dog's issue and remedy that. If your dog is just stressed being in a new situation, you should calmly get them off of you, offer them a treat to calm them down, and have them sit politely beside you until their stress level has subsided (or take them somewhere else so that they can calm down if it is taking a while for them to calm down.) But most of all, please do not just ignore this behavior change.
In order to perfect the proper greeting routine, your dog needs much more practice than that. You can speed up the training process by leaving through the back door and returning through the front door over and over again. When your friends come over, have them do the same. Each time, ask your dog to sit-stay before opening the door. At first his excitement will make it difficult for him to concentrate but after you've repeated this process 10 times, he will calm down and be able to concentrate. Before asking your dog to sit-stay in this distracting and exciting situation, be sure he has a reliable sit-stay in normal, non-stressful situations. And of course you can always just hold the dog in a sit if need be.
Why do dogs jump up? A plausible explanation arises from their ways of communicating with each other. A puppy greeting an adult dog often licks the adult’s muzzle -- a polite, deferential behavior. Dogs, of course, descend from wolves, among whom muzzle-licking is how pups get the grownups to regurgitate food for them. Domestic dogs rarely nourish puppies this way, but muzzle-licking has survived, maybe because deferential behaviors are handy for a social animal. Think of humans saying “No, after you.” Muzzle-licking is also an appeasement behavior -- something you trot out to de-escalate a fight. A human might lift up his hands, palms toward the person he’s arguing with.