I don't think you can throw a whole heap of statements in brackets at the
InputBox function like that. Try using

Then SCTCode = InputBox("1 = Underwater Structure" & vbcrlf & _
"2 = Feeding Structure" & vbcrlf & _
"3 = Transfer Structure" & vbcrlf & _
"4 = Fixed Structure" & vbcrlf & _
"5 = Custom Sturcture" & vbcrlf & _
"Enter Code 1 thru 5: ")