=FIND("@",SUBSTITUTE(A1,"","@",(LEN(A1)-LEN(SUBSTITUTE(A1,"","")))/LEN("")))

Public Function GetLastChars(InputText As Range) As String
    Dim tmp As String, ret As String
    tmp = Replace(InputText.Value, "E:UserImages", "")
    Do While (InStr(tmp, "")) > 0
        ret = ret & Mid(tmp, InStr(tmp, "") - 1, 1)
        tmp = Mid(tmp, InStr(tmp, "") + 1)
    Loop
GetLastChars = ret
End Function