Why does Unity 3.x/4.x fail to start on Windows?

Why doesn't my brand new Unity 3.x/4.x start on Windows?

Unity may fail for different reasons: needs a supported video card, sufficient memory and hard disk space to run. It also needs the Operating System to have the expected drivers, libraries and permissions..

Following is a list of common solutions that have worked before:

  1. Make sure Windows is Up To Date. For this you can use the Windows Update application. Also make sure you have the latests drivers for your hardware. Sometimes they are listed in the Windows Update application, others you have to look for them in the manufacturers website.

  2. DirectX libraries not found. This may throw an error message, such as: "The program can't start because d3dx9_XX.dll is missing from your computer. Try reinstalling the program to fix this problem.". Unity may be requiring a DirectX library that hasn't been found in your OS. See this site for more information: http://windows.microsoft.com/en-US/windows7/Diagnosing-basic-problems-with-DirectX

  3. Data Execution Prevention (DEP) on Windows Vista and above. This does not occur on every machine, but some users have reported DEP can stop Unity from working. To add an exception follow this guideline : http://windows.microsoft.com/en-US/windows-vista/Change-Data-Execution-Prevention-settings, "To turn off DEP for an individual program". Note: It is reported (but not confirmed) that Oct '11 security updates to Windows change the DEP setting to highest and this can stop Unity in it's tracks. Change back to the settings mentioned earlier.

  4. "The application failed to initialize properly (0xc0150002)". Users reported this may occur in Windows XP. A posted solution was to install the Microsoft Visual C++ 2008 Redistributable Package (x86): http://www.microsoft.com/downloads/en/details.aspx?FamilyID=9b2da534-3e03-4391-8a4d-074b9f2bc1bf&displaylang=en.

  5. User permissions. Unity needs to be able to write and read files. Sometimes user privileges disallow this. Try running Unity as an administrator by right-clicking on the icon and selecting: "Run as Administrator". Using the shortcut properties you can set Unity to always run as administrator.

  6. Firewalls, Anti-viruses, other software. Try closing all running programs in Windows before starting Unity. An application may be conflicting with Unity.

  7. Send a bug report. If problems are not reported it's more likely they will not be fixed. Besides, Unity Support may already have an answer for your problem.

  8. Try and see if Unity will start when you choose to run the Project Wizard on start-up. This will help you determine if Unity is crashing because of your project.

  9. Worst case scenario: Re-install Windows. Windows is a very complex piece of software, that can break after a lot of usage, installing-reinstalling software and using utilities that remove system files (e.g registry tweaking, antivirus/antispam removing what it shouldn't, optimizers disabling services, etc.) Some users have found Unity works after reinstalling Windows. Leave this as your last resource.

  10. If you have an kernel level debuggers installed Unity will not open. Please remove your debuggers. Note that the best way to completely eliminate these debuggers is often to re-install Windows.

  11. If you have any unusual USB devices attached to your computer try removing them. Occasionally USB devices can appear as HID devices and cause input problems. Unusual might mean anything that is not a keyboard or mouse.

did you get an error on the unity 2.6 uninstall section? that sometimes causes it to crash if it doesn't uninstall correctly, an easy way to tell this is if you have the same startup picture in the opening, you know the jungle thing? ya that if it's still the jungle island picture and not a army man standing it's not working correctly and reinstalling unity 3.0 may fix it.

I restarted my computer and ran it again and there were no other issues.

Make sure Unity 3 is installed right, A few possible fixes from my usual Diagnosis is to A) Install Java JDK B) Reinstall Unity 3. C) Installing java in general such as JRE D) All of the above.

I had the 0xc0150002 error. I found that downloading both the Microsoft Redistributable C++ library fixed the problem.

Reinstalling Windows isn't really what I consider a way to "fix" the Unity startup crash. That costs too much in man hours to get everything back in working order, plus you may have to wait a day or two for Unity support to add another activation to your Serial Number.

Problem: I upgraded from 2.6 to 3.3. It started fine, then crashed after 5 minutes in an empty scene (well, it did have a camera in it). Now, every time I try to open the program it fails to initialize, providing no error message at all, just a submit bug window.

This is bad. Our project was working fine and we've been at it for 2 years. I've tried everything applicable on the list above.

I re-intalled Unity, and it worked all right! ;)

For 3.30f4. After three tries at install/re-install with full reboots on a VistaHP OS, I tried Solution 4 (install Microsoft Visual C++ 2008 Redistributable Package (x86)) and it worked to get Unity up and running for me. Thanks!

What worked for me on Win XP SP3 was Solution 5. Right click on the shortcut icon and select Properties → Shortcut → Advanced Properties. Check ‘Execute with different credentials’. Now every time I want to run it I have to write the username and password. Thanks anyway!

Hi, thanks for the checklist… In my case, it’s a Windows 7, 64-bit machine, and the problem was that DEP was turned off by default for all programs. After I added ‘Unity Editor’ as an exception, Unity came up just fine :slight_smile: Again, thanks for the checklist, that’s what led me to look at the DEP settings.