To Thunderbird they are not aliases, they are email addresses.

Add them to Thunderbird like any other address.

From the Menu Bar select File-New-Existing Mail Account

Or

From the 3 line AppMenu button, click that and hover over New Message, then select Existing Mail Account

>Add them to Thunderbird like any other address. >From the Menu Bar select File-New-Existing Mail Account

Thanks for your response!

I did the above and it seemed to be a step in the right direction... Only trouble is both, new addresses failed authentication (neither address would login, therefore neither's inbox had any mail).

Not knowing which way to go, I supplied my account password for my daughter's account and left the pwd field blank for my wife's account.

With previous mail clients, simply supplying the 2 alias names WO my account pwd would work... Any more suggestions?

They would need their own password for their own email address.

When they loggon to see their email, they would use a password and that is the same password you need in Thunderbird.

You cannot use your password for your email address to access their email address unless they had deliberately been setup with identical passwords.

Thanx for replying...

They would need their own password for their own email address.

Yes, IF they were independent accounts, but they're not, they're alias accounts under my main account.

I tried both their accounts, one with my pwd and the other W/O any pwd. Both failed...

This is what I THINK is happening: I authenticate with my credentials (pwd & username); from that point I can access both alias accounts using either of their usernames... This is how I was able to set-up & use Outlook Express for so many years. We were all using WinXP back then, we're all on Win7 & Win10 now, though. Unfortunately, Outlook Express is outdated & no longer supported.  :(

I have Comcast and have created additional accounts for family members to use. They are actually email accounts with their own individual passwords. I have no access to them from my main account or with my password. Contact Comcast for help with using their system. When you figure that out add them to Thunderbird like any other address with their own info and password.

So, if I understand you all correctly, I (as well as my wife & daughter) can no longer access their eMails with Thunderbird unless they login with their own PWDs, even though, in the past (with other mail clients) I could?

BTW, I did call Comcast and asked for help accessing my other eMail accounts. I got sent to an incorrect department (evidently) that tried to sell me a $199 PC cleaning fee that would take "2-3 hours". They quickly reduced the fee to $99 when they found out that I was handicapped/disabled.

When we (my wife & I) told them we couldn't/wouldn't afford that either, they quickly dismissed the offer & terminated their remote desktop software that they had running.

Do the new addresses work at the Comcast webmail page? What username and password do you use there. Did you ask Comcast how these additional email addresses work while you had them on the phone?

When your wife and daughter want to logon to webmail account to see their emails, they will use the email address and a password to get access.

Whatever password they use to get access - that is the password required by thunderbird.

Please can you confirm the following. Have you set up each email address as a separate mail account ? 'Menu icon' > 'New Message' > 'Existing Mail account'

Airmail said

Do the new addresses work at the Comcast webmail page?

I don't know if they do or not, I haven't tried IMAP, I'm set-up with POP. Is this why I'm having difficulties? I prefer using POP, but I'm willing to convert to IMAP, if needed.

What username and password do you use there.

For my account, I use my credentials (my email address & my password), this works flawlessly.

In the past, to gain access to my wife's eMail, I would still login with my credentials but use my wife's eMail address as the user name (in a separate field of Outlook Express & in Win Live Mail). I would do the same for my daughter's. This set-up would work flawlessly too.

Did you ask Comcast how these additional email addresses work while you had them on the phone?

No I did not, because they were too busy with their own agenda, IE: selling me a PC cleaning package. They weren't very concerned with why my eMails weren't working... They seemed to think that the reason why these Mails weren't working was because of a virus or malware issue!

At that point, I lost all credability with them. Especially after visiting their site.

I did manage to find some eMail set-up info, but it was only basic stuff, not very detailed at all!

Toad-Hall said

Whatever password they use to get access - that is the password required by thunderbird.

I understand this, but it's not working. I don't know what I'm doing wrong. maybe this is an IMAP/POP issue?

Have you set up each email address as a separate mail account ?

Yes, I have 3 separate eMail accounts in T'bird, mine, my wife's and my daughter's. When I set-up my wife & daughter's accounts in T'bird, I tried setting them up with & W/O a PWD (my login PWD).

Ever since I created these accounts, when I open T'bird, it tries to login, but it fails and I have to <cancel>. Then I'll "get mail" for my account only.

I just now thought I had a brainstorm ... I tried setting my wife's account with my login name (my eMail address) and her credentials as the identity's name & eMail. I thought "this is what I needed to do," (similar to Outlook Express & Win Live Mail) but T'bird rejected these settings citing my account had already been created. (I was in <manage Identities> ) <sigh>

When you get tired of wasting your time go to the Comcast webmail site and set up the additional email addresses and test them. Then add them to Thunderbird as what they are, additional email addresses with their own username and password.