I don't have Ol2007 but Ol2003 and inside a control panel which I leave for you to find I can set the default email to plain text or other. Why not change that?
Do not let "it worked before" stop you cold.
Bob
I'm running Office 2007 on Windows 7. I have an Outlook signature file (html) that embeds an image using a file:// directive. Default outbound format is html. A couple of days ago the mailer stopped converting the file: directive to cid: and embedding the image, so now my signatures have the raw file: with a reference to a local file on my HD -- obviously, that doesn't work. I CANNOT find what setting has been changed to have caused this.
Default e-mail editor is word. A hint may be that when I try to e-mail a document directly out of word it defaults to plain text and I have to set it to html. However, even if I switch to html first, THEN include the signature file, the image processing does not happen.
Again, this has been working for three months. I've checked and the signature files themselves have not changed since December, so I don't believe they are corrupted.
Any hints, clues, assistance would be greatly appreciated.
TIA

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