gormenghast wrote:could anyone advise on what I should do to avoid having content of my emails becoming attachments in the emails I sent out?
If you send signed email to a user that has Outlook or Outlook Express, when you use PGP/MIME, the email will appear as a blank email with two attachments - your html message and a signature (.asc) file. This is a limitation of Oultook and Outlook Express rather than OpenPGP and Enigmail. If you sign a message using inline PGP (ie. Do not use PGP/MIME) then the email will appear as a text email correctly, however if your recepient does not use OpenPGP or PGP software, they will see a lot of scrambled text inline - this is the OpenPGP inline text code.
I would suggest that you use email signing only if the recepient has the software to recognise it, or if they do not use Outlook or Outlook Express. Probably the least invasive way to do this is to use PGP/MIME.
gormenghast wrote:Does it also depend on whether the recipients have an email client or web-based email like yahoo or gmail?
If you are just signing your email, it doesn't matter if the person is using webmail or not - they will still be able to read the main content of the message whether you use PGP/MIME or not. However, they will not be able to verify your signature if you use PGP/MIME. If they use a program such as WinPT, they would be able to verify your signature by copying and pasting an inline PGP message to the program, but it is probably unlikely that people with Webmail would use email signing and encryption very frequently.
In my opinion, it is best to sign your emails using PGP/MIME if your recepients have webmail accounts.
If you are encrypting your email rather than just signing all your outgoing email then you should use inline PGP (do not use PGP/MIME) since it is the most universally compatible method for your email. However, I suspect that you are simply signing all your outgoing mail, and I think the best way to do this is to use PGP/MIME. However, it is not compatible with Outlook and Outlook Express mail clients, so you should consider setting up per-recepient rules to
not sign outgoing mail to recepients you know that use these mail client programs.
Does this help you?