Having an interesting little problem intermittently here in version 4.3. Every so often, I will open up my project and find that every transition from “Any State” to anything else in Mecanim is gone. I haven’t touched those transitions in a while and I’m save-obsessive, so it’s not like I’m forgetting to save my changes. Each time this happens, I re-create them from scratch and they’ll be gone again in about a week.
Any thoughts? I’m admittedly stumped. =)
Are you editing your files from the directory at all? If not then some other program must be messing with them. Or you keep accidently doing something you did not mean to Reimporting the object with the animator sometimes will eff things up.
I haven’t actually done any of those things. Nothing gets reimported and nothing gets touched in the directories themselves. I pop it open, lay lines of code, and not much else at this point. I haven’t had to touch the transitions on that state in the Animator in ages; in fact, I only do anything to that state when I’m re-creating the transitions because they’ve vanished. Strange stuff. I’ll try paying closer attention to what I’m up to, just in case.
I’m noticing this too, and I’m using PlasticSCM for source control (although not integrated into the editor via the Team License). PlasticSCM is telling me that the .controller file has not changed and after closer inspection inside the text-based asset I can see that the transitions are still there, and it would appear that Mecanim is failing to pick them up. Therefore I’m inclined to think this is a bug, but so far it’s not been either annoying or reproducible enough for me to report!
Bump. This has been happening to me for most of 4.x. I’ve reported it but never heard anything back. I can’t reproduce what steps causes an Animator to develop problems. The only commonality are sync layers. My layers that aren’t synced never develop problems with Any State transitions but sync layers will lose their Any State transitions on some sort of random time table.
Same issue has been happening for me too. Anyone have any updates on this?
I’m getting this issue as well. I’m using tortoiseSVN with metafiles turned on and reverting doesn’t seem to fix this. I would really like for this to be addressed…
I have been getting this for a long while, but it’s extra annoying now that I’m adding stuff to my Animator and twice today it happened. I have to relink about 30 things.
Only once did I suspect it would happen, when I received a red warning in the console that I didn’t understand while working on the animator. Sure enough saved reloaded and they were gone.
Has anyone found a solution for this? It’s basically a show stopper. I’ve already lost an entire afternoon replacing missing transitions, and now I just found that Unity has removed about 30 transitions from Any State, all of which had fairly complex transition criteria.
I can’t just revert the controller, as it looks like they have been missing for a while, and many other changes have been made to other sub-state machines. 
I’ve just managed to recover my transitions. Contrary to an earlier post, my source control did indicate that the controller had changed in the past.
All of the transitions were still there in the YAML, but the section defining the order of transition IDs had become empty.
Basically, this :
m_OrderedTransitions:
data:
first: {fileID: 0}
second:
has become this :
m_OrderedTransitions:
data:
first: {fileID: 0}
second:
So some new transitions from Any State (in a different sub-state machine) had overwritten all of the existing transitions IDs. I manually merged the 2 lists back together, and it works again - the transitions have returned will all of their associated data.
There isn’t a huge amount to go on here currently.
I’ve asked the Mecanim guys to have a look at this thread.
Looking at this thread it would seem that CareLevelZero is in a pretty perfect position to submit a bug report. If you let me know the ID, I’ll try and get QA to reproduce it locally…
What was the bug id?
If you can write down this warning, if you ever see it again, it could be useful for diagnosing the problem. Remember it goes into editor.log and editor-prev.log
I jst had the same thing happen to me; it occurred right after I deleted two animations I had just put in und\er the animator; I saved, made a copy of my WHOLE game folder, closed and reopened unity and YUP, they were gone. I am on windows 7 BTW
Bump.
Well, that’s interesting! I read this earlier and thought, “well, that’s interesting, I will keep it in mind for future reference!”. That future reference became a present reference about an hour ago. We’ve now lost our any state transitions.
We just started getting this issue too. Our technical artist has them on his end but mine are missing. We tried re-committing the controller over SVN and manually copying it, no luck.
You can just do a manual merge of the file before and after the problem. If you look inside it, you’ll find that the transition definitions are all still there, the actual assignments are missing. Go to the m_OrderedTransitions property and look for the fileID: 0 tuple. Its list will be empty. Copy and paste the entries from the old controller and it’ll work. It hasn’t recurred since, here.
For the benefit of anyone else who reads this thread: I was a bit confused by what Alkis recommended, but after doing some searching I discovered the Asset Serialization option under Editor Settings. If you switch this to Force Text, all your Unity assets, including Animators, will be readable text files rather than binary. You can then “look inside” the files by opening them in Notepad or any other text editor. You will then be able to apply his suggestion, although since we switched to Force Text this transition disappearance problem has been solving itself whenever we commit a new version of the Animator to SVN. 
Thanks Alkis.
Oh, yeah, sorry, been using it for so long that it didn’t even occur to me to mention that I’m implying text serialization!