+Check which COM port the virtual serial port has been assigned to:
+ Device Manager->Ports (COM & LPT)->Teensy USB Serial
+ In brackets it will say which COM port (e.g. COM3)
+
+
+putty works well when using DTR/DSR or RTS/CTS flow control.
+Connection type: Serial
+Serial line: <Your COM port, e.g. COM3>
+Speed: (doesn't matter, it's auto-negotiated)