I have been messing with my configuration.h and configuration_adv.h files in order to free up some memory. Somehow I screwed up the operation of the eeprom plugin and for the life of me I can't figure out what needs reversing.
Specifically, the eeprom plugin runs but only gives me the 'info' tab and none of the other tabs where you set individual parameters.
Thoughts ?
Can I assume that you didn't save revisions of your configuration files for Marlin? (You should consider these important enough to save each time you manage to get a good-working version.)
It's probably good to visit the Marlin repository, search for eeprom and review what things are related to this topic.
LOL ... yes, you can safely assume that .... doooohhhhh
On the bright side, I played around some more (yes, without saving first) and I think I got it
// #define DISABLE_M503
I did not have that line commented out.
Now that it is commented out, things are working again.
Thanks for replying, I messed about with this for a couple of hours last night and was sure I had reversed all changes ... I guess not quite 
It might be simple enough to just go into your Explorer/Finder software, find this folder, right-mouse click on it and choose the Compress/Zip option. It's the cheapest backup I know.