When you try to install Citavi you receive the following error message: "This installation package could not be opened."
The Windows Installer service is disabled.
In the Windows Control Panel under Administrative Tools > Services, check whether the Windows Installer service is enabled. If not, click Start the service:
If that doesn't help, re-register the Installer service:
- Press WIN+R.
- Enter cmd and click OK.
- Enter msiexec /unregister and press Enter.
- Enter msiexec /regserver and press Enter.
- Restart your computer.
- Install Citavi.