You have to set up a complete account and that means setting up a Pop account with it's SMTP at the time of creating the Pop account, but just because you have set up an SMTP for the Pop account email address does not mean you have to use it.

Thanks for clarifying this, but is there any way to insure that ALL my outgoing mail, including stuff from the second account that I "reply" to, will go out with only one of the accounts?

 To be clearer, I have Account #1 and #2. I want to receive from #1 and #2, but only to use #1 as the automatic default for sending mail.

Generally, the 'FROM' email address that gets auto inserted into a Write message is determined by whatever mail account or mail account folder is selected. So if you had selected a pop mail account folder and was reading emails therein and clicked on 'Write, the 'FROM' would automatically be the Pop mail account email address which would use the pop account smtp server for sending.

As I understand it Account1# smtp is the one you want to use to send regardless of whatever FROM is used. Providing the email address of Account2# is allowed to use the smtp email address of Account1# then you can change the server settings as follows. You may need to logon to the webmail account of Account1# email address and set up to allow email address account2#.

In 'Account Settings' > select 'Account name' for the POP account Account2# Bottom right you will find 'Outgoing Server (SMTP)' Do NOT click on the 'Edit SMTP_Server' button - this is not advisable. Instead, click on the drop down option and select the other smtp (default) option. I'm assuming the account1# has the smtp server which is currently set as default.

Once again, your answer was spot-on. No problems anymore.