I wanted to rearange some toolbar buttons and to my astonishment
after releasing the button my button disappeared.
Did I do something wrong?
If so, does anyone know how I can get my original toolbar back?
Version 6 SR22
(6.22.20028.13281, 28-1-2020)
Well, if you Shift+LMB dragged (‘Move’) an individual button out into the Rhino window without dropping it into another toolbar, that is the equivalent of deleting it. You should have gotten a “do you really want to delete this button?” message to confirm. Deleting buttons cannot be undone.
There are a couple of ways you can get this back. If you are using the default workspace and haven’t made any extensive modifications to it you can run the TooolbarReset command in Rhino and follow the instructions - that will bring your entire workspace back to default - but you will also lose any customizations you might have made.
Alternatively, in your folder
C:\Users\<your user name>\AppData\Roaming\McNeel\Rhinoceros\6.0\UI*
Appdata is a hidden folder - to access it type %appdata% at the Windows start button, which will get you to 'Roaming" and then navigate from there.
you will find a file called default.rui.rui_bak which is the backup default toolbar file. Make a copy of that and rename it to something like “Temp_default.rui”. Then from inside Rhino with the workspace that now has a missing button, go to Options>Toolbars and from the Edit menu, choose Import toolbars. Then browse to your temp default file above, and import the entire toolbar which contains the missing button. Then with Ctrl held down (copy), LMB drag and drop just the button back to where it was in the original workspace. It will be copied. You can then close the imported toolbar or even delete it.
" Well, if you Shift+LMB dragged (‘Move’) an individual button out into the Rhino window without dropping it into another toolbar"
Nope, just moved it 1 place to rearrange. Therefore I do not understand why it dissapeared. I tryed to make a new button but it I can not drag it to the spot I wanted. They are just disappering.
and Yes… It was a custom made button with a complex macro 
Can you see the whole toolbar? Sometimes they do not drop into the place you want and get placed at the end… If you did not get a delete warning they should still be there somewhere.
Yes I see the whole bar. I even unlocked it, to drag it “stand alone” and enlarged it to see if it rolled off somehow.
No, no warning at all. As I wrote, even newly made buttons disappere when dragging.
OK, I’m at a loss to say what’s happening then - I’ve never seen buttons get deleted without the warning message coming up…
FOUND them!!!
Apperently moved them to another toolbar 
And that one was full so they dropped off the visual part