Netscape 7.1 Adding email addresses

I have been using Netscape 7.1 several years to send and receive email. Recently I set up additional email accts with a new provider and entered all the information including pop server and smtp server. The new accounts all have the same password with ISP and same pop/smtp; however, I can only send from one address. When I try to send from another of the addresses, I get a message saying "an error occurred while sending email. The server responded: 5.7.1 Authentication required to send email as (XXXXX...ISP version of my email address). Please verify that your email address is correct in your mail preferences and try again." The email addresses are entered correctly, they can receive email, but only one of them can send email. I spoke to my ISP to verify that the accts are active and they said the problem was something related to a Netscape password. Does anyone have a clue what he means...or more directly, how to solve this problem?

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I think I have narrowed it down. My motto: If at first you dont succeed.....

Can someone help me overcome the final problem?

In the window where you set up the smtp server, there is a box to be clicked to enter password and id. If I enter either of the id's, it will let me send only from that email address. If leave the box unchecked and enter neither of the id's, it will not let me send from any address. I can enter each address id with the same smtp, but when I want to send email from that address, I have to go into the smtp setup and change that one to 'default.' I did not have this problem with my previous email setup. Help?!?

 

That has been confusing, and later related programs, not necessarily Netscape, have made some changes to make think simpler.
I had AOL, and, I had to authenticate the sender. For this purpose, I added another account smtp, after clicking the Advanced button. I had to enter exactly the same account and port info, except for the username, which, also had a check mark.
Now, I have not had NS7.1 for a couple of years, so I am not sure which Advanced button you should chek, but, I think that it is the one belonging to the username, the same page where you enter the username, check to send HTML, and also add your signature. You will have the chance to select the SMTP tab, and then you will be presented with identical smtps, or so they look like in the list. Generally, the top one is the default, or the one which allowed you to send before. The second one, not default, is the one that you just added. If you select the second one, the smtp authentication login will come up when you try to send mail with the second account. Klutzi but it works.
You can add other smtps, but select which one you want to use.
If you can't find what I said, let me know, I may be able to come up with a link and some pictures. But, as long as you stick with 7.1, you will have that problem (7.2 is not much better, except that you have to go to Server Settings|Advanced to make your selection.

 

Ty

Thank you for your response. Believe me, I know how difficult it is to put all this stuff in writing. What you have described is exactly the best work-around I have been able to figure out. (but no one at tech support ANYWHERE could even identify the problem...sigh!) That means that when I want to send from the 2 addresses I use less frequently, I will have to enter the smtp set-up screen/menu and change the default; then change it back for most frequent sending address. A pain, but...at least a way to do it. TY again.

 

With the way I described you should not have to make any further changes. To illustrate this, I will tell you what I had. None of my AOL accounts were ever default, but I had added to the SMTP list the two or three of them so that I had a non-AOL SMTP which was default, and listed below:
smtp.aol.com (wth username1)
smtp.aol.com (with username2)
smtp.aol.com (with username3).
The trick was to match the correct smtp with the correct account. After doing that I had no further problem, in having the correct match. also, check this setup sample