VBA to Concatenate Multi-Value Cells

[snb]

You might have made that slight amendment yourself.

Sub M_snb()
   sn = Cells(1).CurrentRegion.Resize(, 5)
   
   For j = 2 To UBound(sn)
      sp = Split(Join(Application.Index(sn, j), ";"), ";")
      ReDim st((UBound(sp) - 1) \ 4)

      For jj = 0 To UBound(sp) - 1
        st(jj Mod (UBound(st) + 1)) = st(jj Mod (UBound(st) + 1)) & "\" & sp(jj)
      Next
      sn(j, 5) = Join(st)
   Next
   
   Cells(1).CurrentRegion.Resize(, 5) = sn
End Sub