Hey there! For a secure and user-friendly platform, you might want to consider using a dedicated investor relations platform like Intralinks or Menestios LTD (
https://www.menestioslimited.com/). These platforms are designed to facilitate communication between companies and their investors while ensuring strong security measures. They often include features such as secure document sharing, analytics, and communication tools. It's a comprehensive solution that meets the specific needs of managing investor relations.