The three characters � appear to correspond to the bytes EF BF BD (in hex), which I understand to be the utf-8 encoding of the Unicode character U+FFFD meaning use a replacement character.

So, I appears that something like this may be occuring. Original sent as eg: iso8859-1 but erroneously treated as utf-8, converting the non-ASCII characters to U+FFFD, When subsequently interpreted with the original encoding, the corrupted characters appeared as �.

Is the original sent copy in your 'Sent' folder showing this issue? Do you receive emails with that issue ?

If the recipient then forwards (both inline and as attachment) or replies to that email containing those characters, do you see any of these symbols in the returned email?

Please post an image showing what you are currently using in 'fonts & encodings' - like image below. 'Menu icon' > 'Options' > 'Options' > 'Display' > 'Formatting' tab click on 'Advanced' button.

I assume you have saved a copy of the sent email which upon receipt had issues. Select email in 'Sent' folder and click on 'more' > select 'View Source' Below the headers, but before the actual email, you should see something like the following, please copy what you see and paste it into this forum question. Note, there will be additional section as both plain text and html may be present, but I'm hoping what you post will look very similar to what is shown below.

Example: MIME-Version: 1.0 Content-Type: multipart/alternative;

boundary="------------28A4NNFD72DF5B3A834C84FFD"

This is a multi-part message in MIME format.

Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit

Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: 7bit

If you do not mind, could you send a copy of the same email to the following email address - note I do not use it as a rule, but sometimes it helps to see what encoding is going on. email: mail at anje dot co dot uk

Thanks for the reply. No the original does not show the symbols only the receiver. Occasionally I receive emails with the same symbols but mostly from colleagues using Thunderbird as well.

Yes both Forwards and Replies also show the symbols when sent.

I have tried all of the western and utf codes in trying to fix the problem but to no avail.

Some examples of sent email headers where receiver had these symbols: 1. From - Mon Nov 14 09:57:18 2016 X-Mozilla-Status: 0001 X-Mozilla-Status2: 00800000 X-Mozilla-Keys: Subject: Fwd: Fwd: Malus and pyrus import [SEC=UNCLASSIFIED] References: <[email protected]> To: John Morton <[email protected]> Cc: Lynnell Brandt <[email protected]> From: Gavin Porter <[email protected]> X-Forwarded-Message-Id: <[email protected]> Message-ID: <[email protected]> Disposition-Notification-To: Gavin Porter <[email protected]> Date: Mon, 14 Nov 2016 09:57:08 +1000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101

Thunderbird/45.4.0

MIME-Version: 1.0 In-Reply-To: <[email protected]> Content-Type: multipart/mixed;

boundary="------------54C415A674C8F368124F1DE2"

This is a multi-part message in MIME format.

Content-Type: multipart/alternative;

boundary="------------BCFFB7BC480952B3E1813295"

Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit

2. From - Mon Nov 21 16:08:09 2016 X-Mozilla-Status: 0001 X-Mozilla-Status2: 00800000 X-Mozilla-Keys: Subject: Fwd: FW: Apple & Pear Australia v Pink Lady America S APCI 2015 0127-

Listed for Judgment

References: <PS1PR0601MB134056748E5F0E3BDB23D81F8DB50@PS1PR0601MB1340.apcprd06.prod.outlook.com> To: John Morton <[email protected]> From: Gavin Porter <[email protected]> X-Forwarded-Message-Id: <PS1PR0601MB134056748E5F0E3BDB23D81F8DB50@PS1PR0601MB1340.apcprd06.prod.outlook.com> Message-ID: <[email protected]> Disposition-Notification-To: Gavin Porter <[email protected]> Date: Mon, 21 Nov 2016 16:08:05 +1000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101

Thunderbird/45.4.0

MIME-Version: 1.0 In-Reply-To: <PS1PR0601MB134056748E5F0E3BDB23D81F8DB50@PS1PR0601MB1340.apcprd06.prod.outlook.com> Content-Type: multipart/alternative;

boundary="------------ADBDD0BCA501D8DF2CF68516"

This is a multi-part message in MIME format.

Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit

3. From - Mon Oct 31 07:52:33 2016 X-Mozilla-Status: 0001 X-Mozilla-Status2: 00800000 X-Mozilla-Keys: Subject: Re: Message from To: John Morton <[email protected]> References: <[email protected]>

<[email protected]>
<8D097C7C9E1103409CDBCCA714CB2B890B662BCF@SBS2011.starfruits.local>
<8D097C7C9E1103409CDBCCA714CB2B890B69872B@SBS2011.starfruits.local>
<[email protected]>
<[email protected]>
<[email protected]>

Cc: 'Pattullo's Nurseries | Cole' <[email protected]> From: Gavin Porter <[email protected]> Message-ID: <[email protected]> Disposition-Notification-To: Gavin Porter <[email protected]> Date: Mon, 31 Oct 2016 07:52:30 +1000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101

Thunderbird/45.4.0

MIME-Version: 1.0 In-Reply-To: <[email protected]> Content-Type: multipart/alternative;

boundary="------------B2B581460EF90455628A8003"

This is a multi-part message in MIME format.

Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit

Thanks for your help looking into this issue Cheers

I received the email. I notice the following: The original email appears to have been originally created in MSWord, which can cause various formatting issues as copy pasting into Thunderbird also imports a huge amount of formatting which can bloat the email size and sometimes effect the reply user imput. It may be better to use the 'paste without formatting' option or create the email in thunderbird using Thunderbirds formatting bar options.

In the source view, I see 'Content-Transfer-Encoding: 8bit'. I would expect to see either 'Content-Transfer-Encoding: 7bit' or 'Content-Transfer-Encoding: quoted-printable'

Please try the following to see if we can force the use of 'quoted-printable'. 'Menu icon' > 'Options' > 'Options' > 'Advanced' > 'General' tab

• click on 'Config Editor' button - it will tell you to be careful :)
• In top search, type: mime
• locate this line: mail.strictly_mime
• If the Value = 'false'
• double click on that line to toggle the Value to True
• close the window - top right X
• click on 'OK'

Then please send me a second email - identical to the first one you sent, so I can compare results.

Some info at link, section 'Low Level Concepts' - 7-bit data vs 8-bit data http://www.sendmail.com/sm/open_source/docs/email_explained/#

Thx for looking at this, its appreciated. The original sender of the email (John) uses MS Outlook and the others in the email thread wouldn't use MS Word that I know of, but don't know for sure. We certainly don't use MSWord for any email text generation and other emails we have sent have been generated in Thunderbird and sent with the same result when received, so not sure if the MSWord issue is a constant also. 2nd email has been sent to you. Thanks again. Cheers

Another example from a reply from Thunderbird to an email received (sender uses MS Outlook). Thx

From - Wed Oct 12 16:42:43 2016 X-Mozilla-Status: 0001 X-Mozilla-Status2: 00800000 X-Mozilla-Keys: Subject: =?UTF-8?Q?Re:_Description_for_the_Peachcot_variety_=e2=80=98Vaiolet?=

=?UTF-8?B?4oCZICgyMDA4LzE0NCkgW1NFQz1VTkNMQVNTSUZJRURd?=

To: Barkat Mustafa <[email protected]> References: <E1F30B6F09039B449434A68CEF8E0CAB0163529B@CBR1PEXC02.production.prod> Cc: "anfic(Orcharding for the Future)" <[email protected]> From: Gavin Porter <[email protected]> Message-ID: <[email protected]> Disposition-Notification-To: Gavin Porter <[email protected]> Date: Wed, 12 Oct 2016 16:42:38 +1000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101

Thunderbird/45.4.0

MIME-Version: 1.0 In-Reply-To: <E1F30B6F09039B449434A68CEF8E0CAB0163529B@CBR1PEXC02.production.prod> Content-Type: multipart/mixed;

boundary="------------5F8A5AEB4DEA5D02CEBA965C"

This is a multi-part message in MIME format.

Content-Type: multipart/alternative;

boundary="------------996518199C406AE6FE2DCC5B"

Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit

The second email was received and all looks correct. There are no � characters.

The view source now shows: Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8; format=flowed

Content-Type: multipart/related;

boundary="------------F73D86391D19EF781844DCB7"

Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8

So this is now correct as the 'quoted-printable' is now working.

If your recipient called 'Claire' can also read all correctly then could you mark my previous comment (which discusses 'mail.strictly_mime') as the 'Chosen solution'.

Thank you very much, this has worked a treat. Much appreciated. Cheers