I have SM on two different Mac machines, one very old, one kinda old.
Very old one has very old SM. 2.49b I think. New one is near current.

I use "roadrunner" as ISP which is Spectrum, owned by Charter.

I have had the same settings on both machines for more than ten years.
Email set-up for POP/SMTP (in/out)

Just today, neither machine could send mail, and I got a pop-up inside
SM that stated;

Alert!

An error occurred while sending mail. The mail server responded: 550
5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The email
address you are sending as must match the email address you used to
auth. Please check your SMTP settings. AUP#Out-1500. Please verify that
your email address is correct in your Mail preferences and try again.

After discussing it at length w/their IT help, even though BOTH
computers suddenly had the issue, we went through the SMTP settings line
by line. It was discovered that I needed to change my security setting
to STARTTSL and to use a password.

They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
suddenly, today, I had to add that security info to my SMTP settings in
both SM on both machines, for it to function. And yes it now functions.

Fascinating.

GW

Geoff Welsh wrote:
> I have SM on two different Mac machines, one very old, one kinda old.
> Very old one has very old SM.  2.49b I think.  New one is near current.
>
> I use "roadrunner" as ISP which is Spectrum, owned by Charter.
>
> I have had the same settings on both machines for more than ten years.
> Email set-up for POP/SMTP   (in/out)
>
> Just today, neither machine could send mail, and I got a pop-up inside
> SM that stated;
>
> Alert!
>
> An error occurred while sending mail. The mail server responded:  550
> 5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The email
> address you are sending as must match the email address you used to
> auth. Please check your SMTP settings. AUP#Out-1500.  Please verify that
> your email address is correct in your Mail preferences and try again.
>
> After discussing it at length w/their IT help, even though BOTH
> computers suddenly had the issue, we went through the SMTP settings line
> by line.   It was discovered that I needed to change my security setting
> to STARTTSL and to use a password.
>
> They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
> suddenly, today, I had to add that security info to my SMTP settings in
> both SM on both machines, for it to function.  And yes it now functions.
>
>
> Fascinating.
>
> GW

Security settings was my first guess while I read your post.
My second guess is that they have had this requirement for a while now
(look at their documentation) but had still permitted the older access
method, someone then noticed and pulled the plug without telling anyone.

I have six email addresses with five providers. The SMTP settings are:
Port Connection Security
587 STARTTLS - four providers
465 SSL/TLS - the other one

One of those four is gmail and they have OAuth2 as Authentication
method, the others are all "Normal password".

As to reading mail, gmail requires SSL/TLS with OAuth2, all of the
others need SSL/TLS with "Normal password". I'd check your Server
Settings there as well, just in case.

It has been several years since those email providers started insisting
on encrypted passwords, I think all of them warned users that it was
coming but it is so long ago I'm no longer sure.
A few people have had similar problems here in the last couple of years,
even ignoring OAuth2 when gmail changed their requirements.

Don Vito Martinelli wrote:
> Geoff Welsh wrote:
>> I have SM on two different Mac machines, one very old, one kinda old.
>> Very old one has very old SM.  2.49b I think.  New one is near current.
>>
>> I use "roadrunner" as ISP which is Spectrum, owned by Charter.
>>
>> I have had the same settings on both machines for more than ten years.
>> Email set-up for POP/SMTP   (in/out)
>>
>> Just today, neither machine could send mail, and I got a pop-up inside
>> SM that stated;
>>
>> Alert!
>>
>> An error occurred while sending mail. The mail server responded:  550
>> 5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The email
>> address you are sending as must match the email address you used to
>> auth. Please check your SMTP settings. AUP#Out-1500.  Please verify
>> that your email address is correct in your Mail preferences and try
>> again.
>>
>> After discussing it at length w/their IT help, even though BOTH
>> computers suddenly had the issue, we went through the SMTP settings
>> line by line.   It was discovered that I needed to change my security
>> setting to STARTTSL and to use a password.
>>
>> They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
>> suddenly, today, I had to add that security info to my SMTP settings
>> in both SM on both machines, for it to function.  And yes it now
>> functions.
>>
>>
>> Fascinating.
>>
>> GW
>
> Security settings was my first guess while I read your post.
> My second guess is that they have had this requirement for a while now
> (look at their documentation) but had still permitted the older access
> method, someone then noticed and pulled the plug without telling anyone.
>
> I have six email addresses with five providers.  The SMTP settings are:
> Port  Connection Security
> 587   STARTTLS - four providers
> 465   SSL/TLS  - the other one
>
> One of those four is gmail and they have OAuth2 as Authentication
> method, the others are all "Normal password".
>
> As to reading mail, gmail requires SSL/TLS with OAuth2, all of the
> others need SSL/TLS with "Normal password".  I'd check your Server
> Settings there as well, just in case.
>
> It has been several years since those email providers started insisting
> on encrypted passwords, I think all of them warned users that it was
> coming but it is so long ago I'm no longer sure.
> A few people have had similar problems here in the last couple of years,
> even ignoring OAuth2 when gmail changed their requirements.

Having checked my various email histories, one provider introduced the
requirement in early September 2006 and another at the start of 2014. I
can't find any emails for the other two non-gmail providers announcing
the change so I probably deleted them years ago. At least one of them
offered both "encrypted" alongside "unencrypted" for years, I'd noticed
and selected "encrypted" so I will have been happy ignoring and deleting
their warning mails. No idea about the other one.

I find it amazing that your email provider had not introduced this
requirement years ago. The one which made the switch at the start of
2014 is a bit like aol.com in that they have a lot of non-technical
users so they delayed making the change as long as they could.

Geoff Welsh wrote on 31-Jul-23 11:01 PM:
> I have SM on two different Mac machines, one very old, one kinda old.
> Very old one has very old SM.  2.49b I think.  New one is near current.
>
> I use "roadrunner" as ISP which is Spectrum, owned by Charter.
>
> I have had the same settings on both machines for more than ten years.
> Email set-up for POP/SMTP   (in/out)
>
> Just today, neither machine could send mail, and I got a pop-up inside SM
> that stated;
>
> Alert!
>
> An error occurred while sending mail. The mail server responded:  550
> 5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The email
> address you are sending as must match the email address you used to auth.
> Please check your SMTP settings. AUP#Out-1500.  Please verify that your
> email address is correct in your Mail preferences and try again.
>
> After discussing it at length w/their IT help, even though BOTH computers
> suddenly had the issue, we went through the SMTP settings line by line.
> It was discovered that I needed to change my security setting to STARTTSL
> and to use a password.
>
> They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
> suddenly, today, I had to add that security info to my SMTP settings in
> both SM on both machines, for it to function.  And yes it now functions.
>
>
> Fascinating.
>
> GW

Since 2021, afaics based on an archived file with email server settings
(file is dated Nov 2021) my RR email account configured in SeaMonkey for
POP3 has been using SSL/TLS for incoming and STARTTLS for Outgoing.
- The Port afaik were not changed in Nov. 2021(995 and 587) nor the
authentication(Normal Password).
- All email accounts in SeaMonkey are configured to specifically use the
email provider's SMTP server settings.
- The RR email account uses the full email address as the username in
both incoming/outgoing

As a test, in another windows logon user profile with SeaMonkey(latest
build release version) setting up the same RR account without STARTTLS in
the Outgoing server yields a popup message that the server timed out.

As another poster noted, it's possible the backend allowing different
security(or no security) was recently turned off, but in my case security
SSL/TLS and STARTTLS has been required since at least Nov. 2021.

Note: That requirement is also contrary to apparently current Spectrum/RR
Help articles which indicate SMTP settings are SSL/TLS or no security
instead of STARTTLS.
e.g.
<https://www.roadrunneremail-login.com/blog/roadrunner-email-pop-server-settings/>

--
....w¡ñ§±¤ñ

....w¡ñ§±¤ñ wrote:
> Geoff Welsh wrote on 31-Jul-23 11:01 PM:
>> I have SM on two different Mac machines, one very old, one kinda old.
>> Very old one has very old SM.  2.49b I think.  New one is near current.
>>
>> I use "roadrunner" as ISP which is Spectrum, owned by Charter.
>>
>> I have had the same settings on both machines for more than ten years.
>> Email set-up for POP/SMTP   (in/out)
>>
>> Just today, neither machine could send mail, and I got a pop-up inside
>> SM that stated;
>>
>> Alert!
>>
>> An error occurred while sending mail. The mail server responded:  550
>> 5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The email
>> address you are sending as must match the email address you used to
>> auth. Please check your SMTP settings. AUP#Out-1500.  Please verify
>> that your email address is correct in your Mail preferences and try
>> again.
>>
>> After discussing it at length w/their IT help, even though BOTH
>> computers suddenly had the issue, we went through the SMTP settings
>> line by line. It was discovered that I needed to change my security
>> setting to STARTTSL and to use a password.
>>
>> They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
>> suddenly, today, I had to add that security info to my SMTP settings
>> in both SM on both machines, for it to function.  And yes it now
>> functions.
>>
>>
>> Fascinating.
>>
>> GW
>
>
> Since 2021, afaics based on an archived file with email server settings
> (file is dated Nov 2021) my RR email account configured in SeaMonkey for
> POP3 has been using SSL/TLS for incoming and STARTTLS for Outgoing.
> - The Port afaik were not changed in Nov. 2021(995 and 587) nor the
> authentication(Normal Password).
> - All email accounts in SeaMonkey are configured to specifically use the
> email provider's SMTP server settings.
> - The RR email account uses the full email address as the username in
> both incoming/outgoing
>
> As a test, in another windows logon user profile with SeaMonkey(latest
> build release version) setting up the same RR account without STARTTLS
> in the Outgoing server yields a popup message that the server timed out.
>
> As another poster noted, it's possible the backend allowing different
> security(or no security) was recently turned off, but in my case
> security SSL/TLS and STARTTLS has been required since at least Nov. 2021.
>
> Note: That requirement is also contrary to apparently current
> Spectrum/RR Help articles which indicate SMTP settings are SSL/TLS or no
> security instead of STARTTLS.
> e.g.
>
> <https://www.roadrunneremail-login.com/blog/roadrunner-email-pop-server-settings/>
>
>

If you change from Unencrypted to SSL/TLS or STARTTLS, the port number
changes - different ones in each case.
When you say "in my case security SSL/TLS and STARTTLS has been required
since at least Nov. 2021", are you sure. You can be sure that they have
been *supported* since at least that date, but not that they were
necessarily mandatory. I was an early adopter for password encryption
options, the thought of sending my password over the 'net in plain text
curdles my brain - and I prefer it uncurdled.

oh, and my one account which was SSL/TLS, I checked today and noticed
that both SSL/TLS and STARTTLS were supported for SMTP so I changed it
to match the others.

As an aside, at least that email provider does not accept TLS 1.0 or
1.1, so Seamonkey has to permit 1.2 and/or 1.3.
That's under Options -> Privacy & Security -> SSL/TLS.
It appears I don't permit servers to use 1.0 or 1.1 either - they are
known to be inadequate.

Geoff Welsh wrote:
> I have SM on two different Mac machines, one very old, one kinda old.
> Very old one has very old SM.  2.49b I think.  New one is near current.
>
> I use "roadrunner" as ISP which is Spectrum, owned by Charter.
>
> I have had the same settings on both machines for more than ten years.
> Email set-up for POP/SMTP   (in/out)
>
> Just today, neither machine could send mail, and I got a pop-up inside
> SM that stated;
>
> Alert!
>
> An error occurred while sending mail. The mail server responded:  550
> 5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The email
> address you are sending as must match the email address you used to
> auth. Please check your SMTP settings. AUP#Out-1500.  Please verify that
> your email address is correct in your Mail preferences and try again.
>
> After discussing it at length w/their IT help, even though BOTH
> computers suddenly had the issue, we went through the SMTP settings line
> by line.   It was discovered that I needed to change my security setting
> to STARTTSL and to use a password.
>
> They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
> suddenly, today, I had to add that security info to my SMTP settings in
> both SM on both machines, for it to function.  And yes it now functions.
>
>
> Fascinating.
>
> GW

ISP tech support does not know what their IT people are doing.
Had an interesting issue 3 months ago with ATT Fiber. Started getting
TLS handshake issues on my machines running Win 7, Win 10, Mint,
Seamonkey, and Firefox.
It kept getting worse until the WAN network was barely usable. I called
tech support several times and explained the issue, from tech level 1 to
tech level 3. They read from their script: "reboot the comp", etc.
Tech came out and replaced the existing modem with a new one. No
change. None of them ever heard of Mint Linux. They said it was my
machines and to upgrade to Win 11. I told them it was an ATT issue, not
mine. I started looking into cable and was going to dump ATT when a few
weeks later the ATT issue magically corrected itself on all my machines.
It has been good for the last month.

Don Vito Martinelli wrote on 01-Aug-23 4:16 PM:
> ...w¡ñ§±¤ñ  wrote:
>> Geoff Welsh wrote on 31-Jul-23 11:01 PM:
>>> I have SM on two different Mac machines, one very old, one kinda old.
>>> Very old one has very old SM.  2.49b I think.  New one is near current.
>>>
>>> I use "roadrunner" as ISP which is Spectrum, owned by Charter.
>>>
>>> I have had the same settings on both machines for more than ten years.
>>> Email set-up for POP/SMTP   (in/out)
>>>
>>> Just today, neither machine could send mail, and I got a pop-up inside
>>> SM that stated;
>>>
>>> Alert!
>>>
>>> An error occurred while sending mail. The mail server responded:  550
>>> 5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The email
>>> address you are sending as must match the email address you used to
>>> auth. Please check your SMTP settings. AUP#Out-1500.  Please verify
>>> that your email address is correct in your Mail preferences and try
>>> again.
>>>
>>> After discussing it at length w/their IT help, even though BOTH
>>> computers suddenly had the issue, we went through the SMTP settings
>>> line by line. It was discovered that I needed to change my security
>>> setting to STARTTSL and to use a password.
>>>
>>> They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
>>> suddenly, today, I had to add that security info to my SMTP settings
>>> in both SM on both machines, for it to function.  And yes it now
>>> functions.
>>>
>>>
>>> Fascinating.
>>>
>>> GW
>>
>>
>> Since 2021, afaics based on an archived file with email server settings
>> (file is dated Nov 2021) my RR email account configured in SeaMonkey
>> for POP3 has been using SSL/TLS for incoming and STARTTLS for Outgoing.
>> - The Port afaik were not changed in Nov. 2021(995 and 587) nor the
>> authentication(Normal Password).
>> - All email accounts in SeaMonkey are configured to specifically use
>> the email provider's SMTP server settings.
>> - The RR email account uses the full email address as the username in
>> both incoming/outgoing
>>
>> As a test, in another windows logon user profile with SeaMonkey(latest
>> build release version) setting up the same RR account without STARTTLS
>> in the Outgoing server yields a popup message that the server timed out.
>>
>> As another poster noted, it's possible the backend allowing different
>> security(or no security) was recently turned off, but in my case
>> security SSL/TLS and STARTTLS has been required since at least Nov. 2021.
>>
>> Note: That requirement is also contrary to apparently current
>> Spectrum/RR Help articles which indicate SMTP settings are SSL/TLS or
>> no security instead of STARTTLS.
>> e.g.
>>
>> <https://www.roadrunneremail-login.com/blog/roadrunner-email-pop-server-settings/>
>>
>>
>
> If you change from Unencrypted to SSL/TLS or STARTTLS, the port number
> changes - different ones in each case.

Not entirely - in SM on this device(for email accounts)
For POP3: Changing from Unecrypted(in SM the term is *None* which users
Port 110) to STARTTLS, the port remains as 110. Changing from *None* to
SSL/TLS changes the port to 995

For SMTP when adding a new RR unique SMTP, *None* uses the previously
configured default SMPT port number. Changing from *None* to STARTTLS
leaves the port number intact. Changing from *None* to SSL/TLS changes
the port to 465.

> When you say "in my case security SSL/TLS and STARTTLS has been required
> since at least Nov. 2021", are you sure.

Already covered that for the op - "it's possible the backend allowing
different security(or no security) was recently turned off"

In my case, I can only indicate what my notes in my archived file for my
RR email server settings show that SSL/TLS not supported.
Having said that, are you aware their are multiple server names for RR
accounts where the server is TimeWarnerm, Charter, RR,
Brighthouse(multiple with U.S. state abbreviation unique prefixes xx.rr.com
-

> You can be sure that they have
> been *supported* since at least that date, but not that they were
> necessarily mandatory.  I was an early adopter for password encryption
> options, the thought of sending my password over the 'net in plain text
> curdles my brain - and I prefer it uncurdled.

Did that apply to Spectrum/Charter/RoadRunner ?

--
....w¡ñ§±¤ñ

....w¡ñ§±¤ñ wrote:
> Don Vito Martinelli wrote on 01-Aug-23 4:16 PM:
>> ...w¡ñ§±¤ñ  wrote:
>>> Geoff Welsh wrote on 31-Jul-23 11:01 PM:
>>>> I have SM on two different Mac machines, one very old, one kinda
>>>> old. Very old one has very old SM.  2.49b I think.  New one is near
>>>> current.
>>>>
>>>> I use "roadrunner" as ISP which is Spectrum, owned by Charter.
>>>>
>>>> I have had the same settings on both machines for more than ten
>>>> years. Email set-up for POP/SMTP   (in/out)
>>>>
>>>> Just today, neither machine could send mail, and I got a pop-up
>>>> inside SM that stated;
>>>>
>>>> Alert!
>>>>
>>>> An error occurred while sending mail. The mail server responded:
>>>> 550 5.1.0 <(totally-correct)@hawaii.rr.com> sender rejected. The
>>>> email address you are sending as must match the email address you
>>>> used to auth. Please check your SMTP settings. AUP#Out-1500.  Please
>>>> verify that your email address is correct in your Mail preferences
>>>> and try again.
>>>>
>>>> After discussing it at length w/their IT help, even though BOTH
>>>> computers suddenly had the issue, we went through the SMTP settings
>>>> line by line. It was discovered that I needed to change my security
>>>> setting to STARTTSL and to use a password.
>>>>
>>>> They swear that THEY HAVE NOT CHANGED ANYTHING on their side, but
>>>> suddenly, today, I had to add that security info to my SMTP settings
>>>> in both SM on both machines, for it to function.  And yes it now
>>>> functions.
>>>>
>>>>
>>>> Fascinating.
>>>>
>>>> GW
>>>
>>>
>>> Since 2021, afaics based on an archived file with email server
>>> settings (file is dated Nov 2021) my RR email account configured in
>>> SeaMonkey for POP3 has been using SSL/TLS for incoming and STARTTLS
>>> for Outgoing.
>>> - The Port afaik were not changed in Nov. 2021(995 and 587) nor the
>>> authentication(Normal Password).
>>> - All email accounts in SeaMonkey are configured to specifically use
>>> the email provider's SMTP server settings.
>>> - The RR email account uses the full email address as the username in
>>> both incoming/outgoing
>>>
>>> As a test, in another windows logon user profile with
>>> SeaMonkey(latest build release version) setting up the same RR
>>> account without STARTTLS in the Outgoing server yields a popup
>>> message that the server timed out.
>>>
>>> As another poster noted, it's possible the backend allowing different
>>> security(or no security) was recently turned off, but in my case
>>> security SSL/TLS and STARTTLS has been required since at least Nov.
>>> 2021.
>>>
>>> Note: That requirement is also contrary to apparently current
>>> Spectrum/RR Help articles which indicate SMTP settings are SSL/TLS or
>>> no security instead of STARTTLS.
>>> e.g.
>>>
>>> <https://www.roadrunneremail-login.com/blog/roadrunner-email-pop-server-settings/>
>>>
>>>
>>
>> If you change from Unencrypted to SSL/TLS or STARTTLS, the port number
>> changes - different ones in each case.
>
> Not entirely - in SM on this device(for email accounts)
> For POP3: Changing from Unecrypted(in SM the term is *None* which users
> Port 110) to STARTTLS, the port remains as 110.  Changing from *None* to
> SSL/TLS changes the port to 995
>
> For SMTP when adding a new RR unique SMTP, *None* uses the previously
> configured default SMPT port number. Changing from *None* to STARTTLS
> leaves the port number intact. Changing from *None* to SSL/TLS changes
> the port to 465.
>
>> When you say "in my case security SSL/TLS and STARTTLS has been
>> required since at least Nov. 2021", are you sure.
>
> Already covered that for the op - "it's possible the backend allowing
> different security(or no security) was recently turned off"
>
> In my case, I can only indicate what my notes in my archived file for my
> RR email server settings show that SSL/TLS not supported.
> Having said that, are you aware their are multiple server names for RR
> accounts where the server is TimeWarnerm, Charter, RR,
> Brighthouse(multiple with U.S. state abbreviation unique prefixes xx.rr.com
>  -
>
>> You can be sure that they have been *supported* since at least that
>> date, but not that they were necessarily mandatory.  I was an early
>> adopter for password encryption options, the thought of sending my
>> password over the 'net in plain text curdles my brain - and I prefer
>> it uncurdled.
>
> Did that apply to Spectrum/Charter/RoadRunner ?
>

Nope, I have several accounts with different providers and all (except
gmail) adopted the same solutions. None of them are Spectrum/Charter/RR
but they were confronted with the same problem and fixed it in the
standard way.
As you pointed out, their documentation says that you can encrypt or not
encrypt, but it appears to be out of date.

Don Vito Martinelli wrote on 02-Aug-23 3:02 PM:
> ...w¡ñ§±¤ñ  wrote:
>>> You can be sure that they have been *supported* since at least that
>>> date, but not that they were necessarily mandatory.  I was an early
>>> adopter for password encryption options, the thought of sending my
>>> password over the 'net in plain text curdles my brain - and I prefer
>>> it uncurdled.
>>
>> Did that apply to Spectrum/Charter/RoadRunner ?
>>
>
> Nope, I have several accounts with different providers and all (except
> gmail) adopted the same solutions.  None of them are Spectrum/Charter/RR
> but they were confronted with the same problem and fixed it in the
> standard way.
> As you pointed out, their documentation says that you can encrypt or not
> encrypt, but it appears to be out of date.

The Spectrum-Charter-RR support info being inaccurate is most likely due
to the reason I noted - with over a dozen servers due to acquisitions of
carriers across their current service area - one setting for all the
different servers doesn't apply.

Best approach for those with Spectrum/Charter/TimeWarner/Brighthouse is
to look for current 3rd party articles on server names and settings
before fumbling with email configuration in SM.

--
....w¡ñ§±¤ñ