To prevent software conflicts that can lead to Sage Peachtree Error 18, you can: 1. Keep your software and operating system up to date with the latest versions and patches. 2. Install software from trusted sources to ensure compatibility and reliability. 3. Avoid installing conflicting applications that can interfere with Sage Peachtree's operations. 4. Regularly review and manage user permissions to ensure proper access control. 5. Educate users about safe computing practices and avoiding actions that can lead to software conflicts.