Duplicate Case Error means you have defined two cases with the same value in the switch statement. You are probably looking at your code thinking "but they are all different." To you they are different. To the complier they look much different.
You have defined case statements using the character notation. Single quotes are meant for characters, not strings. Without seeing how you defined textBuff[], I could be wrong about the following: you are probably only comparing one character from textBuff[] (whatever character is at element #8) to whatever constant value the complier generates for the "junk" inside of the single quotes.
Read up on strings.