Unity Editor Undo not Working

Unity Engine
1

Hi there

I have a project for over 1.5 years that Started on Unity 4, then upgraded to Unity 5, and I’ve been upgrading on each Patch Release… everything fine until a couple patches ago, before 5.1
on one of those releases the Undo property broke and I get this error:

MissingFieldException: Field ‘UnityEditor.UndoPropertyModification.propertyModification’ not found.
UnityEditor.Undo.InvokePostprocessModifications (UnityEditor.UndoPropertyModification[ ] modifications) (at C:/buildslave/unity/build/artifacts/generated/common/editor/UndoBindings.gen.cs:173)

So we had to upgrade because of some fixes needed on one Patch, and keept working with the project like that… but it’s been like 2 months since we can’t do CTRL + Z on Editor… and is getting really annoying.

I can’t go back to a previous version because of dependencies.

Any idea on how to fix this?

2

I also have the same problem, do you recommend to go back to the previous version. Is that possible?