DFU Issue: Getting "DFU failed with error: Cannot convert, number too large: 281474976710656."

Question

Hi, 
 I just recently started getting an error when I try to perform a DFU. I have been able to perform the DFU successfully many times in the past, but have been running into a new issue. The issue is that when starting a DFU onto a nrf52832 that already has an application loaded, I'm getting the error "DFU failed with error: Cannot convert, number too large: 281474976710656." on the nRF Connect log. 
 If I start with an erased nRF52832, load the bootloader using Segger Embedded Studio, then do a DFU, I can load and run the app without issue. The issue occurs once I try to use DFU again to update with a new file. 
 I haven't changed any of the DFU or bootloader related code from when it was working to when I started seeing the issues. 
 I'd greatly appreciate any suggestions or pointing to the right direction. 
 Thank you! 
 
 Setup: Windows 10, Segger Embedded Studio, Nordic nRF Connect with BMD-300 Eval Kit, SDK v15.2, nRF52832

luimot · Accepted Answer

OK, figured it out, just writing the answer here for anyone else. 
 Clues from other posts about DFU were that the MAC address is increased by one for the DFU service. I realized that the unit I was using had the all the flash erased and so was using FF:FF:FF:FF:FF:FF as it's MAC address. The number from the error above ( 281474976710656 - 1) = 0xFFFF FFFF FFFF. Once I programmed a normal MAC address, the issue went away and I could use the DFU service again.