cdukes - your function should work provided that all of the characters in the string are in fact letters. But if you have punctuation marks and/or digits, then your function will fail.
That being said, if the question is in fact, Are all letters within the string uppercase? then your function will fail. But if the real question is Does the string only contain uppercase letters?, then your function should be ok.
What I don't understand, if why can't you simply do the following statement:
Dim IsAllUpper as Boolean
IsAllUpper = (UCase(str) = str)
Good Luck
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