Before launching the installer, you must prepare Windows 11 to handle legacy software frameworks. Skipping these steps will cause the setup wizard to freeze or fail immediately. 1. Enable Legacy .NET Frameworks

The CATIA installer will try to install VC++ 2005 and fail. Prevent this.

Click and select Let Windows Update download the files for you . Restart your computer once the installation finishes. 2. Disable Windows Defender SmartScreen Temporarily

Open the folder, then navigate to the Intel_a or win_b64 folder (depending on your installer package). Find the file named Setup.exe . Right-click Setup.exe and select Properties . Go to the Compatibility tab.

Follow these steps precisely to ensure the installation wizard copies all file registries correctly to Windows 11. Step 1: Run the Installer in Compatibility Mode Locate your CATIA V5 R21 installation folder. Right-click on setup.exe and select . Navigate to the Compatibility tab.

Ensure your computer name does not contain special characters or spaces. CATIA R21 prefers simple alphanumeric names. 🖥️ Step 3: Graphics & Resolution Fix

: If the installer does not launch, right-click setup.exe , go to Properties > Compatibility , and set it to run for Windows 7 .

Windows 11 machines utilize modern graphics cards (NVIDIA RTX, AMD Radeon RX, or Intel Iris Xe) that process legacy OpenGL commands poorly. Adding an environment variable forces Windows to manage memory allocation for CATIA correctly. Press Win + X and select .

Right-click the CATIA V5 R21 desktop shortcut and choose . Go to the Compatibility tab.

Choose the standard installation components. If you do not have a separate license server, you will need to install the License Server component included in the installation package.

Before running the installer, you must configure Windows 11 to accept legacy software architecture. 1. Enable .NET Framework 3.5

To install CATIA V5 R21 on Windows 11, follow these steps: