ChemDraw: Installation fails due to Windows Installer running in background

Details:-

Some users may experience repeated installation failures of ChemDraw on Windows 11, even when:

• They have administrator privileges, and

• Antivirus software has been disabled.

Root Cause

In certain cases, the Windows Installer service (msiexec.exe) is automatically running in the background at system startup.

• This behavior is not typically user-configured.

• It prevents the ChemDraw installer from executing properly, as the installer cannot obtain the required access while another Windows Installer process is already active.

• The behavior appears to occur in some Windows 11 environments and may be related to OS-level configurations.

Resolution / Workaround

1. Open Task Manager (Ctrl + Shift + Esc).

2. Under the Processes tab, locate Windows Installer (msiexec.exe).

3. If it is running, right-click and select End Task.

4. Re-run the ChemDraw installer.

   • The installation should now proceed without issues.

Prevention

To prevent Windows Installer from automatically running at startup:

1. Press Windows Key + R, type services.msc, and press Enter.

2. In the Services window, locate Windows Installer.

3. Double-click the service to open its properties.

4. Set Startup type to Manual (default) rather than Automatic.

5. Click Apply → OK, then restart the computer.

🔹 This ensures the Windows Installer service only runs when required by an installation, instead of starting automatically with Windows.