The HTML format is not supported by all email clients. Microsoft Outlook 2007 supports both plain text messages and HTML emails that contain links, formatting and graphics.

Email Formats in Outlook Outlook offers plain text, rich text and HTML design code email formats so that you can choose the most appropriate format for your email messages.

If the Mail app of Windows is displaying its emails in raw HTML data or code instead of the regular readable format, follow these solutions to resolve the issue.

Outlook email format messed up? Maybe you need to fix formatting in Outlook. Set default to to Hyperlink Markup Language (HTML), Rich Text Format (RTF) or Plain Text.

Twitter has changed from a plain text format to full HTML for follower notification emails.