Split requires AT LEAST two parameters... the string to split, and what to split on.... you gave it the first, and nothing else. That's what the error message is telling you.... it's looking at all the versions of split overloads, and none match the one you tried to use.
Split can be used one of two ways... either as a String.Split method, which requires two parameters at least, or as stringVariable.Split which only requires one at least ... the character to split on.... again, you haven't used Split in the appropriate way.

-tg