1. Please access to the following URL to click 「ダウンロード」. 

https://www.thunderbird.net/en-US/

※The Thunderbird downloading page of the most adequate version of your OS will be chosen automatically. 

※After downloading, a donation screen will appear, but you can close it with the X button.

2. Please run the downloaded file The program will be downloaded and the installation will be booted.(Managing authority will be required.) 

3. Please click 「次へ」 as the setting up screen will come up. 

4. Please choose 「標準インストール」 for type of setting up and click 「次へ｣. 

6. Installation will start. 

1. Please access to the following URL to click 「ダウンロード」. 

https://www.thunderbird.net/en-US/

※The Thunderbird downloading page of the most adequate version of your OS will be chosen automatically. 

※After downloading, a donation screen will appear, but you can close it with the X button.

3. The screen of right chart will come up. 

Please drag and drop the Thunderbird icon in the left side to tight folder. 

4. Please boot up the Thunderbird from the application. 

5. The message as the right chart says will be output.Please click ｢開く｣ . In case the access permission to contact came up, please click ｢許可しない｣. 

The procedure to install Thunderbird to macOS is completed.