I have installed version 4.0 in a different folder than version 3.5.6 but now when I run 3.5.6 I receive an error with Unity crash:
“type==kMetaAssetType pathName.find (“library/metadata”) !=0”
The error doesn’t happen if I ask to open a new project, but as soon I open an existing project it crashes.
Does anyone experience the same problem?
This message is usually caused by opening a 4.0 project in 3.5.
4.0 projects are not backwards compatible.
No I am using only projects never opened in 4.0. Probably there is still some reference to 4.0 in th register even if I have uninstalled version 4.0
Thanks
Ok. Are you using the 4.0 version released on the website?
yes this was the adress: Start Your Creative Projects and Download the Unity Hub | Unity
But my problem is that I cannot use version 3.5.6. Sometimes I was able to run it without crashes, but as soon as I tried to import one of my package or asset it crashed.
Thanks
Do you get the same error message when 3.5.6 crashes?
I never had error in 4.0 onli in 3.5.6. I uninstalled version 4.0 and reinstalled 3.5.6.
They were always in different folder and hard disk. Also I created just a demo project to use with 4.0 to prevent damage to my existing projects made with 3.5.6. I was very carefull with instalation and project use as I knew that some problems could arise with the new version. So the first thing I did, was to create a copy of a project to open it with version 4. Thanks Cecilie
After removing every referencies to unity 4 in the register, I followed the suggestion of another user in the forum i.e. remove or rename bootcamp’s project folder (installed by unity 4) and version 3.5.6 works without crash at start. I know it is strange, but this worked also for me.
Had the same problem
Its caused by 3.5 trying to open the last opened project which would be a 4.0 project.
On a Mac you can hold down [option] while opening Unity 3.5 and it’ll let you choose which project to open.
Not sure about the shortcut in Windows.
Windows : Hold alt key while Unity opens. Click on icon then hold alt while unity starts to avoid windows alt+click combos.
Obviously the first thing I did…
To make it work it was necessary to rename the bootcampproject name. I am not the only one that experienced this.
Thanks anyway
Sorry my reply was for the response I quoted and meant as an informational post about how Windows does it, not meant as a suggestion with your issue.
Good luck though.
I rollback from version 4.0 to 3.5.6, I got the same problem, all I did was just removing the folder C:\Users\Public\Documents\Unity Projects\4-0_AngryBots manually, and that’s all… my version 3.5.6 now works fine.
I had the same issue, thank you alejogn, your solution worked perfectly:smile:
I’ve started getting this same error,
Fatal error!
type == kMetaAssetType pathName.find (“library/metadata”) !=0
Yes I have 4.01 and 3.5.7 installed concurrently, but I’ve had no problems running projects in either of them until now.
I get the error and subsequent crashes when installing some assets from the Asset Store window. So far there are just two that I’ve come across, a model pack (BITGEM’s Skeleton Pack and RageSpline). Is it caused by asset packages being exported from 4.x? (I understand Skeleton Pack has Mecanim data so that wasn’t particularly surprising).
edit: It appears RageSpline’s MaDDoX has been suffering this for a while:
http://forum.unity3d.com/threads/157108-RageSpline-2D-Vector-Graphics-for-Unity-v1-5-Released/page4?p=1179742#post1179742
it worked 
but projects i made with 4 doesn’t work :S
If you are using external version control, this can be caused by using *.meta files generated by Unity 4 in a Unity 3.5 project. In your file browser, just search the project for *.meta and delete all the meta files (Disclaimer: you may want to make a backup first!). Unity will automatically regenerate all the meta files for 3.5 on startup and the crash should go away.
thanks dude for this solution bpp
