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I am not a computer guy.  I have been using Roundcube for a long time and my current version is 1.6.6.  Something changed this afternoon.  I was logged in the the user interface changed.  The list of emails is on a vertical plane and the message texts are to the right.  Previously the list of emails was horizontal and above message text.  How do I revert back to the previous display? TIA

Hi everyone,
I use roundcube webmail for professional use. I send over 20 emails every day, sometimes that can get higher than 50. Every time I need to send a high number of emails per day, I receive a 24 hours notice stating that the e-mail could not be delivered.
It doesn't seem to have a pattern: this happened when I used Outlook and the web client on the browser, rebound emails are sent to known people (for exemple, my boss) o people I have an ongoing conversation or brand new people.

Email is definitely my main tool for work and I cannot keep resending +15 emails everyday on top of my usual workload. Here is what the rebounded notification says:

This message was created automatically by mail delivery software.
A message that you sent has not yet been delivered to one or more of its
recipients after more than 24 hours on the queue on box5580.bluehost.com.

The message identifier is:     1rzZeI-002ink-2u
The date of the message is:    Wed, 24 Apr 2024 12:14:46 +0200
The subject of the message is: =?UTF-8?Q?Re=3A_Su_viaje_a_Jap=C3=B3n_-_Septiembre_/_Yoitabi_Tra?=
 =?UTF-8?Q?vel?=

The addresses to which the message has not yet been delivered are:

  [client address]
    host 34.217.196.71 [34.217.196.71]
    Delay reason: SMTP error from remote mail server after end of data:
    450 zx2cr2XzVHHoAzx2crcvzb - <[my address]> server temporarily unavailable AUP#MXRT
  [boss address]
    (ultimately generated from info@yoitabitravel.com)
    host 34.217.196.71 [34.217.196.71]
    Delay reason: SMTP error from remote mail server after end of data:
    450 zx2cryxIdiKqRzx2crPZQb - <[my address]> server temporarily unavailable AUP#MXRT

No action is required on your part. Delivery attempts will continue for
some time, and this warning may be repeated at intervals if the message
remains undelivered. Eventually the mail delivery software will give up,
and when that happens, the message will be returned to you.
Reporting-MTA: dns; box5580.bluehost.com

Action: delayed
Final-Recipient: rfc822;[client address]
Status: 4.0.0
Remote-MTA: dns; 34.217.196.71
Diagnostic-Code: smtp; 450 zx2cr2XzVHHoAzx2crcvzb - <[my address]> server temporarily unavailable AUP#MXRT

Action: delayed
Final-Recipient: rfc822;[boss address]
Status: 4.0.0
Remote-MTA: dns; 34.217.196.71
Diagnostic-Code: smtp; 450 zx2cryxIdiKqRzx2crPZQb - <[my address]> server temporarily unavailable AUP#MXRT
Return-path: <[my address]>
Received: from box5580.bluehost.com ([162.241.218.178]:32574)
    by box5580.bluehost.com with esmtpa (Exim 4.96.2)
    (envelope-from <[my address]>)
    id 1rzZeI-002ink-2u;
    Wed, 24 Apr 2024 04:14:46 -0600
Received: from 90.red-81-44-210.dynamicip.rima-tde.net ([81.44.210.90])
 via 90.red-81-44-210.dynamicip.rima-tde.net ([81.44.210.90])
 by webmail.yoitabitravel.com
 with HTTP (HTTP/1.1 POST); Wed, 24 Apr 2024 04:14:46 -0600
MIME-Version: 1.0
Date: Wed, 24 Apr 2024 12:14:46 +0200
From: =?UTF-8?Q?Sara_S=C3=A1nchez-Escobar?= <[my address]>
To: [client's name] <[client's address]>
Cc: Info <[boss address]>
Subject: =?UTF-8?Q?Re=3A_Su_viaje_a_Jap=C3=B3n_-_Septiembre_/_Yoitabi_Tra?=
 =?UTF-8?Q?vel?=
In-Reply-To: <620430721bf492336f7b93d245b08524@yoitabitravel.com>
References: <CABh=jQJ4pB89W++F+ZeyR_T4rMC7vzdqp6r41R0Pp+F=oRJHJA@mail.gmail.com>
 <017301da7b80$1a5a8060$4f0f8120$@yoitabitravel.com>
 <041107bb6179880f2aa6438f526be4b1@yoitabitravel.com>
 <CABh=jQL+PZCvYHHUbSg07hjE1r=n2ZkbkwZdVGyt49=BO_goUQ@mail.gmail.com>
 <620430721bf492336f7b93d245b08524@yoitabitravel.com>
User-Agent: Roundcube Webmail/1.6.0
Message-ID: <9ad5fd0d30aaf2fc989154e7f058fa73@yoitabitravel.com>
X-Sender: [my address]
Content-Type: multipart/alternative;
 boundary="=_c3a53d08114532e873c848fb51b5704c"

If someone could help me out on this, I'd be very grateful. Or even redirect me to support.

Thank you!

Hello JohnDoh,

I very much appreciate your response.  I forwarded it to my webhost and unfortunately, they informed me that since I am on a shared server I cannot make this change because it would apply to all others on the same server!  Disappointing!
In case the designers at Roundcube are monitoring this forum and are interested, I'm attaching a comparison of my Roundcube webmail (at top) and my Yahoo mail (at bottom).  In reality it looks like a much lighter pale blue on the screen as opposed to this screen grab -- but you can get the picture.  In fact, under certain lighting conditions I can barely see it at all! -- whereas the Yahoo blue is quite obvious and legible.

Thanks again!

Hello, everyone.

I'm experiencing an issue with Outlook email delivery where emails cannot be received by external email addresses. However, sending emails internally works fine. This problem has been going on for 2 days, and my internet service provider's team has not yet found a solution. I would greatly appreciate any assistance from you all.

Thank you very much.