My office in Petaling Street are those 4 storey building. Back then when the company was still young, the company only occupied the first 3 floors (including the ground floor) leaving the 4th floor as a storage area. However, after the management decided to expand its business, only did they started to hire more people, thus moving the old furnitures and archieved documents to awarehouse nearby.
One near experience my colleague was one particular night when she was the last one to leave the office. Although she remembered to shut off all lights and air-con that particular night, my boss (who never fails to be the first to arrive) reminded my colleague the very next morning that she forgot to shut off all the electricity. My colleague was stunned but she did not mention anything. The next day, the same thing happened. My colleague made particular note to off all switches but my boss still came in the morning with the air-con fully in service.
At first, everyone thought that there was something wrong with the air-con and asked experts to have a look at the problem but even the experts were baffled as they could not find any problems with the air-con. The only explanation we could give was that it was on “timer” mode. Funny thing? The air-con gives this problem “as and when it feels like it”.
There was also another time my colleague heard a lady laughing eerily when he had to do overtime. At the same time, there were chairs getting pushed around upstairs when it was very obvious that the only people in the office where another 2 more colleagues with him at the same floor. The moving chairs and laughing woman wouldn’t stop and in the end, he and his colleagues decided to call the night quits and ran out of the office as fast as they could.
I guess its also worth to mention that typing sounds are also often heard after 9pm.
Source : spookycorner.com