Windows Launch Issues (cx_Freeze errors)

Some Windows users experience issues when launching OpenShot Video Editor, specifically an error dialog which contains the title, cx_Freeze: Python error in main script. This almost always indicates that a required DLL needed by OpenShot is missing.

OpenShot is compatible with Windows 7, 8, and 10 (but not Windows XP). We also support both 32-bit and 64-bit versions of Windows (you can find both downloads on the Windows download page). So, I would encourage you to first make sure you have installed the correct version of OpenShot (64-bit vs 32-bit) for your version of Windows.

First, I highly recommend you install any Windows Updates that are pending. Especially any updates related to Microsoft Visual C++ Redistributable packages. Restart your computer, and re-test OpenShot. If OpenShot still fails to launch, please continue this guide.

Next, we need to verify that the following Microsoft Visual C++ Redistributable package is installed: C:\Windows\System32\msvcrt.dll. You can download and install this for either 32-bit or 64-bit versions of Windows. Once you have installed this, restart your computer, and re-test OpenShot. If OpenShot still fails to launch, please continue this guide.

Next, we need to make sure your virus scanner / Windows defender is not blocking the installation of certain DLLs installed by OpenShot, or blocking certain DLLs from executing when launching OpenShot. Carefully disable your real-time virus scanning temporarily, re-install OpenShot, and attempt to launch OpenShot again. If this works, then you likely need to add some rules to your virus scanner to ignore OpenShot files. Re-enable your virus scanner. If this step doesn't help, please continue this guide.

Finally, this is going to take some troubleshooting to determine which DLL file is missing from your computer. Before we continue, you will need a program called Dependency Walker. It is a free download, so please take a moment and install the appropriate version for your version of Windows.

1. Install Dependency Walker
2. Launch Dependency Walker
3. Drag the following files into Dependency Walker, one at a time, and wait for them to load:
   • C:\Program Files\OpenShot Video Editor\launch.exe
   • C:\Program Files\OpenShot Video Editor\libopenshot.dll
   • C:\Program Files\OpenShot Video Editor\libopenshot-audio.dll
   • C:\Program Files\OpenShot Video Editor\Qt5Gui.dll
   • C:\Program Files\OpenShot Video Editor\avcodec-57.dll
4. Look for any missing DLLs. You can collapse the list of dependencies found using the [-] and [+] icons. Look at each of the above files, and scan over any missing dependencies. Sometimes false positives are listed, so be patient and scan the entire list.
5. If you think you have found the missing DLL, be very careful, and Google ways to restore that file, or re-install that file from a safe destination (i.e. Windows Update, Microsoft.com, or other reliable site). Don't use a random DLL download website.
6. If you successfully replace the missing file, and OpenShot now launches successfully, please let me know which files you fixed (so I can better improve the OpenShot installer): jonathan@openshot.org.

Still no luck? My final recommendation is to create a new Windows users called "OpenShot User", and login to that Windows account/profile. Re-install OpenShot as this new user, and attempt to launch OpenShot. If this successfully launches, then most likely your other user has something corrupted in their profile.