email to external recipients delivered as plain text
I am using Thunderbird with a MS exchange work server. All email sent as HTML to external recipients not on the work server are delivered as plain text and I can't figure out why. When using my work laptop and Outlook sending messages to the same recipients they are delivered as HTML messages. These known recipients have HTML enable and I sent it to my gmail account to check as well. Settings for HTML are enabled (see attachment).
All Replies (2)
I don't think there is any intrinsic Thunderbird/Exchange limitation. I have a similar set up and am able to send to external correspondents using HTML.
Are your messages modestly formatted and therefore have no requirement for HTML? Is Thunderbird just being economical and not using HTML because it doesn't need to? Maybe there is a policy setting there that applies only to the SMTP aspects of your Exchange server, which might not apply with Outlook because it uses a proprietary protocol.
What settings do you have under Tools|Options|Composition|General→Send Options?
Send Options have "send messages as plain text if possible" not checked and I have tried "send messages in HTML anyway" and send messages in both plain text and HTML". I get the same result. I don't know whether there could be some sort of policy setting on the SMTP aspects of the exchange server. I did try another client (Em Client) and I get the same result as with Thunderbird.