No contact XC43 after sending program or clone. Cycling power several times corrects issue.

I have also noticed this problem multiple times on XC43 as a service tech.

Sounds like the symptom when first updating to XC4 firmware 1.03, included in IQANdesign 6.07 See blink code description in Appendix B:

One of these blink-codes is after bios update (not needed on newer modules) and one is for the 1.03 update.