This is a very recent story, one that has happened to my boyfriend, first in July, then a second incident two days ago.
Background information first: He has lived in his home since 1981 and it was built in the 1970s. He has had no paranormal experiences in the house before this and to my knowledge, neither has anyone else.
My boyfriend Jim was getting food from the freezer in his garage and he exited though the small door that leads to the utility room in the extension of his house. As he tried to close the door quietly and gently (it is self-closing and slams with a very loud bang), it seemed to pull back on its hinges (into the garage). He pulled it towards him, fighting what he felt was a large force holding the door. He let it go completely and it still creaked back on itself, whereas normally it would slam. He peered into the garage, but it seemed darker than usual and he could see nothing. He wrenched the door hard and as he did so, he heard 'a man's low, hollow groan' from behind the door 'at male head height'. Then he heard the main garage door shudder as if something had smashed into it.
Then two nights ago he was on his laptop in the dining room, which is also an extension, which connects to the living room via French doors. He heard tapping from inside the walls and tried to ignore it, assuming it was mice. Then it seemed to get more urgent and almost like it was tapping out the Morse Code. He tried to decipher where it was coming from - it sounded like it was coming from the wall above the French doors. He went to his room to look out the window - you can see the roof of the extension from there, as it is directly above the French doors. As he opened the window he saw a light anomaly 'like a flame or a glowing spider's web of mist.' This light flew towards a tree in the garden, making a high pitched moan as it went, before disappearing.
Could this be a ghost? He lost his dad to cancer 11 years ago, so it could be the spirit of his father, but it seems that both incidents involved something trying to get in.