Opening MSG files in Thunderbird can be challenging since the application doesn't natively support the MSG format. These files are typically created by Microsoft Outlook and contain complete email details such as sender data, attachments, metadata, and formatting. Without the right tool, Thunderbird users cannot open or view MSG files directly.

To overcome this limitation, the best solution is to use Cigati MSG File Viewer. This free and easy-to-use software enables users to open and read MSG files on any system without requiring Microsoft Outlook. It supports both single and batch file viewing, allowing you to access all message details, including subject lines, sender information, attachments, and the internal message structure. It's a convenient option for anyone who needs to analyze or extract MSG data before transferring it to Thunderbird.

After viewing your MSG files with Cigati MSG File Viewer, you can export them to Thunderbird-compatible formats such as EML or MBOX. Once converted, the files can be easily imported into Thunderbird using built-in features or add-ons like "ImportExportTools NG.” This method preserves all your email data, attachments, and formatting during migration.

In summary, Cigati MSG File Viewer is the most efficient way to open, view, and convert MSG files for Thunderbird. It saves time, protects data integrity, and eliminates the need for Outlook -- making it the ideal solution for managing MSG files effortlessly.