If you want to open your MSG file in Mozilla T-Bird, then first change your MSG file into an EML file and then open your EML file in Mozilla T-Bird. I suggest you simple software to change your MSG file into an EML file. Download a ToolsBaer MSG to EML Converter. This software has facilities to batch conversions of MSG files. I show you some simple steps to change your MSG files into EML files.
Steps to change MSG files in EML files:
• First download and install the software
• Now you can open this software
• After opening the software you can see the type mode
• Now select the type mode
• After selecting type mode you press the ”BROWSE” button
• After pressing the “BROWSE” button you can select the MSG file
• After selecting the MSG file you can select the OUTPUT file location
• After selecting the file location again you press the “Browse” button
• Now proceed to the next step of changing the MSG files into EML files
After changing the MSG files into EML files, you can easily open your EML files in Mozilla T-Bird
To know more check this site: https://www.toolsbaer.com/msg-to-eml-conversion/