effects credit rating?

[kirakirakit]

I studied out of the contry for one year, and during that time I had trouble accessing my student account as I hadnt set up online banking and they wouldnt help via phone or mail. So, I told them since I was within agreed overdraft I would deal with it upon returning.
When I arrive back in the country , I find the bank has been sending letters to my old place and closed the account! It seemed so rediculous!
Even the man at the desk said, "I dont know why it happened, it justs seemed we couldnt reach you so closed the account". He said the result was I just can't open a new account there...which is fine but I am worried about if this will effect my credit rating, and if so how to improve the situation...