Are you talking about protecting a PDF with a password, and what would your question be

Exactly!

I have Thunderbird and it simply does not link up to my account.

So you're having troubles Emailing a password protected pdf from within the program?  Im not sure why foreign based would be any different for emailing.

Maybe something here will help?  It mentions Thunderbird.

https://proconnect.intuit.com/community/manage-integrations/help/set-or-change-default-email-program...

I personally don't use the Proseries Email function.  I save to PDF then use Bullzip to password protect with a password of my choosing then attach to email like any other file.

Like Lisa I don't use ProSeries for email, as I haven't much luck getting it to work for most years. At one time I used Thunderbird and it worked for a while, then stopped working. I now use Encyro (very reasonable price) for all remote contacts with clients (including signing the 8879)

For my system, the "mailto" protocol needed to be changed:

Settings > Apps > Default Apps (from the left) and on the right, scroll to the bottom > Choose default apps by protocol

Any URL or hypertext where the real path starts with "mailto:" will trigger whatever you assign here. Even web-based gmail will honor this, but there are some other settings to make, including in gmail, for that to bypass a desktop client mail app.