Changing The Value Of A String

I have a string that may consist of one, two or three digits. If it has one digit, I want to append two zeroes to the left of it. If it has two digits, I want to append one zero to the left of it. The string is titled "Result". In this case, the original string was "64" and I wanted to change it to "064".

I tried this, to no avail:

If Len(Result) = 2 Then
zero = 0
Result = (zero & Result)
MsgBox ("The new value for result is " & Result)
End If

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How can I alter the value of a string depending up its length (in this case)?

If I use a new variable, the transfer of value works okay, as so:

If Len(Result) = 2 Then
zero = 0
Result1 = (zero & Result)
MsgBox ("The new value for result is " & Result1)
End If

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