DO NOT COMMUNICATE WITH IT.
I have experienced this. I am not the type to believe at all in such things. Like most of you I thought such things are rubbish.
I was living abroad in South East Asia. We had a maid. She told me that there was a ghost that was calling to her at night. She wasn't afraid and said it as a matter of fact. She just wanted me to know.
I did not believe her, but I would notice some weird sounds at night - namely the sound of heavy furniture being moved in the upstairs flat at about 3am. The flat upstairs was empty with noone living there.
There were times I would walk into the kitchen and notice all the cupboards open - the maid would say it was 'the friend'. I didn't believe her.
One time the maid was not around and I went into the kitchen to make some tea, I left the kitchen for like 20 seconds and returned to get some biscuits and ALL THE CUPBOARDS WERE OPEN. That is when I got a bit freaked out. I rationalised it away, but a friend then told me to try and communicate with it.
The worse mistake I made was acknowledging its existence and trying to 'communicate'. Things got MUCH MUCH worse after that. It would leave lights on, leave taps running. The most terrifiying thing it did was it would shake the bedroom door or knock on it as if it was trying to get in. DH once thought there was really someone and he opened the door and of course there was nothing.
We got a priest, a pastor in, a psychic in- my maid did some weird thing going around the flat with burning sage. Nothing worked. We left when it started trying to scare the kids (they were babies). We did find out that a maid had previously killed herself in the flat six years before we moved in.
I haven't had any weird experiences since, but I don't dismiss it when people tell me about it.