The AutoClean feature in Outlook removes unwanted line breaks

Microsoft Outlook includes the AutoClean feature for plain text formatted messages. The AutoClean feature removes extraneous hard returns that have been entered into plain text messages. These hard returns are usually inserted by Internet e-mail gateways as messages travel through them.

AutoClean starts when the following occurs in Outlook:

• You open an item.
• You preview an item in the Preview pane.
• You right-click to print an item in view.
• You insert a message as text.

The AutoClean feature does not permanently alter the contents of the body of the message. Changes to the message are not saved when the you close the item.

Changes to the message are saved when one of the following actions occur:

• When you reply or forward a message where the AutoClean feature has removed the hard returns, the copy that is sent also has the hard returns removed.
• When you print a message that has the unwanted hard returns, Outlook prints the message without the hard returns.
• If you make changes to the message body after you have run the AutoClean feature and you save the message, the message is permanently altered with the hard returns removed.

AutoClean does not work with messages that have security settings, such as signed or encrypted messages, applied to them.