You've misunderstood what Byte.Parse does. It attempts to convert a string representation of the numbers from 0 to 255 into their 8-bit numerical equivalent. It is exactly the same as Integer.Parse except it produces an 8-bit number instead of a 32-bit number. What you want, I'm assuming, is the Bytes that represent the characters in your string. To do that you would use the GetBytes method of an Encoding object.