Strings can be assigned directly to byte arrays and visa-versa. Remember that Strings are stored in a Multi-Byte Character Set (see Remarks below) so only every other index of the resulting array will be the portion of the character that falls within the ASCII range.
Dim bytes() As Byte
Dim example As String
example = "Testing."
bytes = example 'Direct assignment.
'Loop through the characters. Step 2 is used due to wide encoding.
Dim i As Long
For i = LBound(bytes) To UBound(bytes) Step 2
Debug.Print Chr$(bytes(i)) 'Prints T, e, s, t, i, n, g, .
Next
Dim reverted As String
reverted = bytes 'Direct assignment.
Debug.Print reverted 'Prints "Testing."