diff --git a/robots/little_john/telemetry/code/monitor/serialselect.py b/robots/little_john/telemetry/code/monitor/serialselect.py
index 0825de4..aa2b2e9 100644
--- a/robots/little_john/telemetry/code/monitor/serialselect.py
+++ b/robots/little_john/telemetry/code/monitor/serialselect.py
@@ -38,6 +38,8 @@ def selectserial():
         message = "Please choose a serial port to recieve data through:"
         title = "Found multiple serial ports!"
         serialport = easygui.choicebox(message, title, targetdevs)
+        if serialport == None:
+            return "User cancelled selection dialogue"
     else:
         print("Only found one likely serial device: " + targetdevs[0])
         serialport = targetdevs[0]
--
libgit2 0.21.2