Hello Kevin King,
Thank you for your interest in NXP LPC and MCUXpresso IDE, I would like to provide service for you.
Now, please follow my steps and try again.
1. I find your CMSIS DAP version is a little old
You can update it at first.
1) download lpcscrypt tool and install it.
LPCScrypt v1.8.2|NXP
2) power down the LPC54608 board
Short JP5
Use the USB cable connect J8.
Open PC: Control Panel\Hardware and Sound\Devices and Printers
You will find your board is named as LPC, just like this picture:

3) Open LPCScript, program LPC-LINK2 with CMSIS-DAP window


Press any key, wait the write finished.

4) Power off the boad, remove the short between JP5, check PC: Control Panel\Hardware and Sound\Devices and Printers

Until now, your CMSIS DAP is updated as the new version.
2. Open the SDK I2C example project with MCUXpress

1.) RUN->debug configuration
Please delete the two files under MCU Application

2). Build the project
3). Click debug

You will get this window:

Press OK button
You will enter the debug mode:

Please follow my above steps, and try again.
Any question, just let me know!
@ZhangJennie
Have a great day,
Kerry
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