can somebody tell me how to prevent same questions being repeated in this column?

If the question is of You, it is easy as you could notice and delete the same.

If some one unnecessarily posting same question you can express displeasure in answers even you can report abuse

..........................v

It is common for repeated questions. Because the way each person ask the same or similar question is different. So, if you know that it is the same question, simply redirect the answer which was answered before or copy and paste the same here as the answer.

when you type your question, and before you post it, it will come up with a list of same or similar questions, you can decide to post it anyway, rephrase it by editing it, or give it a miss. i dont think it matters much about the same question being repeated as new people discover answers everyday. hang in there, and just have fun with it. cheers.

Questions may be same, but answers must be different.