With the following code segment the Strings.Len() function is being skipped or not returning a value since the debugger says the variable Test1 is not assigned while the following line with Strings.InStr() function works properly:

```
   sOPCTagItem = opcTagItem.Cells.Value --> assigns "DO1001_Inp_IOFault"    
   sBaseTagItemName = Left(sOPCTagItem, InStr(sOPCTagItem, "_") - 1) --> assigns "DO1001"

   iTest1 = Len(sOPCTagItem)  --> = nothing assigned
   iTest2 = InStr(sOPCTagItem, "_") --> = 7
   iTest1 = iTest1 - iTest2   --> = nothing assigned
   sBaseTagItemExtension = Right(sOPCTagItem, Len(sOPCTagItem) - InStr    (sOPCTagItem, "_"))   --> = nothing assigned

```