I don't have an unwrapped message to test this, but what happens if you change the view_source.wrap_long_lines preference to true?

Tools(or AppMenu/Options)/Options/Advanced/General/Config. editor, copy view_source.wrap_long_lines into the Search, double-click to change it to true, OK, restart TB.

Sounds like a perfect solution -- but that's the way it's been (and is) set... Thanks for the thought.

I tried the method suggested here, and it seems to work with a test message consisting of a single, very long string of text.

I applied your suggestion and tried it on the most recent email I had which failed to wrap some long lines. Its appearance on receipt after forwarding it to myself was unchanged. However, in the forwarding process, there were some lines and handles that resemble those Word adds for tables (they did NOT show in the original email). So I guessed that TB was deliberately (or unknowingly) preserving the object structure in that specific message. I renamed the chrome directory I'd created as part of your solution, and could not force any other long lines to not wrap. So now I guess the message that wouldn't wrap was caused by the structuring used (but not related to TB), and I didn't really need anything else from TB. Your suggestion was what triggered my discovery and so you get the credit for solving it! Thanks so much!

Keep in mind that when you forward an unwrapped message, it's possible to select Edit/Rewrap (Ctrl-R) in the Write window, and that sometimes helps. But as you say, the problem most likely resides with the original message formatting, which is sure to cause problems if it was HTML created in Word.

Rewrapping eliminates all images and formatting- NOT what is needed when you've got a detailed set of instructions complete with images that absolutely requires its formatting to stay intact for clarity.

Agreed, rewrapping is best for adjusting messages that are mainly text, just as setting View/Message Body As/ to Simple HTML or Plain Text sometimes helps with unwrapped received messages.

Any message that contains "a detailed set of instructions complete with images" is probably best conveyed as a pdf, image or doc attachment to avoid the vagaries of HTML formatting, which is not consistent across email programs.

I thought that that point might be raised [hoped it wouldn't], and yes, if I were sending these instructions to the average user I'd do exactly that. In this case, the recipients are likely not skilled enough to deal with attachments and possibly not equipped to open them.

Really, having created a formatted document in another application AND then wanting to copy it intact into an email, you'd think there'd be a reason.

"Yours is not to wonder why; yours is but to do or die" [answer or die :D]

And this part of the discussion wouldn't even have to be had if the rewrap advice were given as 'text wrapping in plain text emails' [careful, this deletes your formatting and images]. I found out the hard way that the rewrap wouldn't help with html.

Incidentally, anyone creating content in Word or similar might consider pasting it into an html editor and checking for the presence of non-breaking spaces ( & n b s p ; ) that stymie line wrapping.