Fn key wont turn off. i have an acer aspire 5100. it was hooked up to a pc keyboard. now that its

Question

i have an acer aspire 5100. it was hooked up to a pc keyboard. now that its not, the Fn key wont shut off. i keep getting the blue symbol on the key instead of the letter. HELP!!!!

the same problem. I get 5 insted i, 6 for o, * for p and so on. I can also get letters, but only when Fn pressed. Sound and back light control works fine