For a non-managed model, here is where to find the serial number:
1. Plug In Ironkey drive
2. Run IronKey.exe
3.Enter password and login to IronKey
4. In the windows System tray (bottom right corner of windows), right click on IronKey icon and select "About IronKey D300"

5. Serial number will be visible here (Highlighted in red box):

For a managed or enterprise model that is not yet activated, here is where to find the serial number:
1. Plug in your IronKey drive
2. Run IronKey.exe
3. When you see the control panel asking for activation code, Hold the" CTRL" key and "Left Click" on the IronKey logo on the top left control panel (Picture below)

4. The Configuration window will pop up with the serial number (highlighted in the red box)
FAQ: KDT-0050918-IK-01