What can I do if Unity keeps crashing on me when I start it?
By default, Unity always loads up the last project that you edited, but you can override this by holding down "Alt" while unity starts. Press and hold it quickly after launching unity, and you'll get an option to select a different project or start a new project.
If the problem is with the project, then this will help make unity usable for you again, although it doesn't much help find out what the actual problem is.
For that, try looking at the Editor.log file after unity crashes which can be found here:
- OS X
- ~/Library/Logs/Unity/
- Windows XP
- C:\Documents and Settings\(current user)\Local Settings emp\UnityWebPlayer\log
- Vista/Windows 7
- C:\Users\(current user)\AppData\Local\Temp\Low\UnityWebPlayer\log
Try starting Unity and immediately after double clicking the icon, press and hold Alt on your keyboard. This will start the "New Project Wizard" from where you can start a new project. By default, Unity opens the last project you've worked on, but there was a problem with this project, it might prevent Unity from opening. This is where you can use the Alt+DbClick method.
If this still does not help you, and you are on a windows box, you should check your DEP-settings. DEP is short for Data Execution Prevention (How to handle DEP in Windows Vista and in Windows 7) and, as the name implies, might prevent an application from running properly.
If you are running windows, this may be an issue with your drivers. Fire up DXDIAG (Start > Run > "DXDIAG") Some users have reported issues with DXDIAG hanging when it gets to Input. Uninstalling the HID drivers has helped resolve this issue for some users
In rare cases where Unity cannot start at all, Unity can be run in "compatibility mode" on Windows.
If you are still stuck, please contact Unity Support: support@unity3d.com or report a bug.
The reason for crashing is probably a problem with the currently active scene (the one Unity will automatically reopen when Unity loads your project). Rename the scene file before starting Unity will open the project but with an empty scene.
Possibly the scene is beyond repair (until there's a bugfix for Unity that makes the scene stop crashing) but at least the rest of your project is workable again. You can now try reimport all assets (menu) save the project and reopen the offending scene if maybe problem is fixed automagically.
I've found the solution to my crash-problem. It had nothing to do with the update to a new version or incompatibilities with older versions!
Actually (with the very quick help of the support), it turned out that Unity is not compatible with some settings of Airfoil (a program that I use for sending music from my PC to remote speakers).
After uninstalling Airfoil, everything went back to normal.
Wow - I would have never thought of that... BIG thanks to the Unity support! <3
In case any Mac OS users land here with the same problem, i.e., "Unity crashes immediately on startup", please try the following.
It requires the root password.
From the terminal:
sudo su
Then run:
/Applications/Unity/Unity.app/Contents/MacOS/Unity
If it says it requires read and write permissions, allow it. It will then go on to import the bootcamp assets and start Unity without crashing.
If not, please contact support@unity3d.com
I myself faced the same issue … and I report the bug to Unity … And I got and answer …
apparently My GPU doesn’t support DX11… I solved it by :
Right click on Unity link → Properties, then make sure You’re in the Shortcut tab. Now you need to add " -force-d3d9" to the target link as shown in attached image. Hit apply and close the window. Now try to open Unity.
**Big thanks to Unity … Excellent Support . **
I had same issue. I fixed it by delete lavasoft softwares from my computer. You can see other solutions here:
try closing monodev if its still open
I had to revert to an old working version, then update little by little WHILE Unity was open.
He could process all the assets and everything turned alright.
sudo apt-get install gnome
Install Gnome and enjoy. I did the same 
I found when I get into a startup crash loop that deleting everything in the Library → ScriptAssemblies folder and letting unity rebuild them on startup fixes the issue
Sollution in my case: Delete the Library and Temp folder in your unity project (client/clientUnity) - that solved the problem. We are using svn by the way.
If this helps anyone else… Had the exact same problem after installing Unity 4.34 here, but none of the above suggestions helped. Turned out to be an Avast Antivirus false-positive - it was moving UnityEngine.dll to the Virus Chest during the installation process. Simply going into the virus chest and un-blocking/restoring UnityEngine.dll fixed the problem.
For whatever reason when running Unity 4.0 in Win7 on Parallels on my Mac, I couldn’t get the Alt-start trick to pop up the new project wizard. This is not an uncommon scenario for Asset Store Submitters to run an old version in a VM. Anyway, I worked around this by launching Unity with the command line option Unity.exe -createproject C:\unityFix
Unity then opens after creating this empty project. Then I turned on “Always Show New Project Wizard” in the preferences.
Hey guys,
Just want to add I was dealing with this issue on windows 8.1 pro 64bit on a lenovo Y410p. This particular laptop model has two graphics cards, an intel integrated graphics and an nvidia GeForce GT 755M. The default behaviour for non game applications is to use the integrated graphics. This caused the application to immediately crash. Manually setting it to use the Dedicated graphics from the nvidia control panel resolved the issue for me. Hope this helps.
Hi Guys,
For the past one week my Unity crashing on opening the Open Wizard,but opening Scenes directly works fine.Then i reported a bug to unity3D, Later i ran Boot time scan in Avast that fixed and unity now running finely,I thinks its because of threat files.But today i just did the CCleaner registry cleaning and found that its the cause for unity not responding.So its my advice to avoid doing Registry fixes or be careful while doing that.Hope this Help you guys,
Regards,
Arun K
After trying everything here (everything was as it should be) I debugged on the device and and found a missing driver for Oculus Audio Spatializer. Turns out when when clicking in the editor inspector to get focus I turned on “Virtual Reality Supported” option under Other Settings.
If you have tried @duck and @NicolajSchweitz answers, then please DOUBLE check your settings. You have to watch where you click in the inspector. You can click all the way over to the right next to the scrollbar and it will toggle a Boolean field or select the field for that line. I wish they would change that so you have to actually click the field (label) name but well what can you do - they still haven’t fixed the MonoDevelop Paste from external source bug.
Hope this helps you, Good Luck!
None of these fixed my problem. What did work however, was uninstalling unity and then removing all traces of it in both my home directory and inside the registry. You can find these places here: Total remove and re-install - Unity Answers
One simple step to try for any project:
Go into the project folder and delete the “Library” and “Temp” folders. Then open the project again and see if it works.
It will take some time “calculating asset hashes” and doing other things it does like the first time you open an existing project. But this approach has worked for me on several different projects where crash-on-load issues came up.