We're calling on all EU-based Mozillians with iOS or iPadOS devices to help us monitor Apple’s new browser choice screens. Join the effort to hold Big Tech to account!

Mozilla サポートの検索

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

詳しく学ぶ

このスレッドはアーカイブに保管されました。 必要であれば新たに質問してください。

How to change default email provider when mailto is not a content type in applications

  • 2 件の返信
  • 6 人がこの問題に困っています
  • 1 回表示
  • 最後の返信者: sillynoa

more options

I recently installed outlook on my machine. Now instead of Gmail as my default email it uses outlook and I want to change it back to Gmail but I do not have Mailto as a content type in apps. Please help.

I recently installed outlook on my machine. Now instead of Gmail as my default email it uses outlook and I want to change it back to Gmail but I do not have Mailto as a content type in apps. Please help.

選ばれた解決策

When I create a new blank Firefox profile, mailto is there by default, so perhaps at some point it got deleted from your download handler/application preferences file. That file can in theory be edited, but since the format is not well documented, it might be simplest to rename that one and have Firefox generate a new one.

Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using

Help > Troubleshooting Information > "Show Folder" button

Switch back to Firefox and Exit

Pause while Firefox finishes its cleanup, then rename mimeTypes.rdf to something like mimeTypes.old.

Restart Firefox and check Options > Applications again. Any luck?


Also, your Firefox reported itself to the forum as version 17, which is no longer secure (Mozilla discloses security flaws after each new release). Is something holding you back from upgrading to Firefox 20? Please let us know so we can suggest solutions or workarounds.

If Help > About Firefox shows Firefox 20.0.1, you may need to clear the preference that is misreporting your version number. See: How to reset the default user agent on Firefox.

この回答をすべて読む 👍 4

すべての返信 (2)

more options

選ばれた解決策

When I create a new blank Firefox profile, mailto is there by default, so perhaps at some point it got deleted from your download handler/application preferences file. That file can in theory be edited, but since the format is not well documented, it might be simplest to rename that one and have Firefox generate a new one.

Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using

Help > Troubleshooting Information > "Show Folder" button

Switch back to Firefox and Exit

Pause while Firefox finishes its cleanup, then rename mimeTypes.rdf to something like mimeTypes.old.

Restart Firefox and check Options > Applications again. Any luck?


Also, your Firefox reported itself to the forum as version 17, which is no longer secure (Mozilla discloses security flaws after each new release). Is something holding you back from upgrading to Firefox 20? Please let us know so we can suggest solutions or workarounds.

If Help > About Firefox shows Firefox 20.0.1, you may need to clear the preference that is misreporting your version number. See: How to reset the default user agent on Firefox.

more options

Worked, thank you for making my day better!