The XDS110 on some F28x LaunchPads are not detected if firmware updated to 3.0.0.33 and power cycled. No issues with eariler versions like 3.0.0.31 and 3.0.0.32.

Grounding the TDO pin of the MSP432E401Y will succeed in forcing the XDS110 to DFU mode and allowing you to reflash the firmware (if needed). Another (easier) workaround is to simply hold down side button S1 on the LaunchPad while connecting the USB cable. With both workarounds, it is necessary to do it each time after the LaunchPad is powered up after being powered down.

Issue was reproduced with an LAUNCHXL-F280039C. There are reports of it impacting LAUNCHXL-F280049C though not consistently reproducible (it may be specific to when the LaunchPad was made, affecting more recently made ones).