No idea what I've done (noob), all of a sudden I can't open and close the different layers. BUT one layer (wing bone) opens and closes ALL layers, so that everything either shows or everything completely disappears. My History is also very limited. This is the file I've been working on for a couple of months and all was working fine all day up until now. I tried closing everything and restarting the computer which didn't help. The wing on the left is the original, the one on the right is just a duplicate. I made a copy of the wing in another file, the layers and history aren't working on that file either. Could I have exceeded some limit, I wonder? I feel like I've wasted the entire day. I hope I can get the layers to work again.

https://www.dropbox.com/s/q9wtgjz868jatm9/LOGO%20WING.svg?dl=0

Hi Valkyrie,

the reason is that you grouped all the feathers into a single group.
Groups can only live on a single layer at once, they cannot spread over several layers.
This is why everything in your drawing is now on the layer Wing Bone.

You will need to ungroup everything again (Ctrl+U, or Ctrl+Shift+G).
Then select all the feathers you want to move back to one of the other layers using Shift+Click.
Use PgUp / PgDown + Shift to move them to the layer where you want them to be.
Repeat for the other layers which are now empty.

(and because of a bug, you will need to readjust the position of the text that you put on path - I think this problem is known.)

Oh okay thanks heaps, Moini! I grouped everything to duplicate. I also tried ungrouping everything but didn't realise that I physically had to go through and re-add them back to their original layers.. Think I will have to make my own troubleshooting list so I remember my mistakes. Thanks again.

You can also duplicate things without grouping them first - it may be more difficult to select them once deselected, though.
Hold the Alt key down to only move the current selection, no matter where you click (so you can move the duplicates 'out of the way', if you need to).