Remove attachments from emails

I am tidying up large attachments in Outlook to reduce the size of the PST file.
In some e-mails the attachment is in the message body. These particular attachments cannot be cut, deleted or otherwise removed, since these controls are greyed out.
How can I remove these attachments?

These messages were received in Rich Text Format (RTF) so the standard method of right clicking on the attachment in the header of the message and choosing “Remove” is not available.

To still be able to remove these attachments you’ll have to double click on the message to open it in its own window. From the Actions menu choose Edit Message. Now you can select the attachment and press Delete.

After this, save and close the message.

Note: When removing attachments, the size of the pst-file will not directly reflect this. Outlook will compress the pst-file automatically when the computer is idle. You can manually force the compression too.