Gmail Error Message on Multiple Sending

Hello
some email addresses may contain unauthorized characters

https://fr.wikipedia.org/wiki/UTF-8

--
At least take the time to respond!
A thank you is appreciated.
Set it to resolved if your issue has been solved. I address everyone informally.

Hello,

It's your font that is not right...

It all depends on how these emails are written...

- On a PC?? or not PC??
- With an email management software, like Outlook or Thunderbird for example...
- Or directly on the Gmail webmail page

You need to find where the characters are hiding... In the settings...

However, I remain surprised... because UTF-8 is the most used in our regions on the Web...

Maybe you are with Orange??

Check this out https://support.google.com/mail/forum/AAAAdi_TnLkHpe3hIRQzA4/?hl=fr&gpf=%23%21topic%2Fgmail-fr%2FHpe3hIRQzA4

Hello, and thank you both for your responses.
To Redbart: I had read the Wikipedia article, but it doesn't provide me with a solution - thanks anyway.
To Jeannets:
I am also very surprised because this is the first time it has happened to me.
It is true that I have reset all my email accounts because the IMAP server kept dropping its connection.
To answer your questions precisely:
The email texts in question are typed on my PC using Outlook
And no, I am not with Orange but with Free.
The account in question is a Gmail account.
The affected addresses work very well on other accounts,
so I don’t know how to search for the offending characters. Thank you for any ideas you might have on this issue.
Best regards
.

Yes, so it's a "long-winded" route through the Outlook menus.

Tools==>Options==>Mail Format===>International Options==>Uncheck "Automatically select encoding for outgoing messages"
And in the box just below, click on the small triangle and select the character encoding for outgoing messages" and choose "Western Windows Alphabet" .... OK validate

There you go, that should be fine... You can also choose other types of encoding like Turkish, Chinese, etc... and "Central European Windows" which might also be suitable...

In short, with this path, you should be able to manage and send your emails

There you go...

So..?? Is it working or not..??

Hello,
My apologies for the late reply, I had to be away.
So, on Outlook 2016, I couldn't find "tools" then options. However, I found "options" under "File", then a "Mail" tab. But unfortunately, there's no "International options" or "Uncheck 'Automatically select encoding for outgoing messages'"
Maybe I'm having vision problems... or brain issues.
Thanks if you can provide me with more details.
Best regards.

Orange circle point in the top left corner. Here is the screenshot of Outlook 2016 "File" and "Home"
So I looked in the help for "International Options" and "Automatically detect encoding for outgoing messages" but couldn't find anything that corresponds.
As for the hair problems, it's Outlook's fault; I'm pulling my hair out.

Oops, the screenshots:
https://www.cjoint.com/c/JHAwHIhlUbq

-- First problem, I don't have Outlook 2016... the screen shown yesterday is that of 2013

-- Your image is hard to read, the text is too small, etc. It would be better to take a screenshot with the "Snipping Tool" or "Screen Capture" in the accessories folder, then upload it to cjoint.com as you did... this also allows you to zoom in on the image while keeping it sharp.

-- I believe I see in your first image, in the blue bar on the left, the word "Options." We should focus more on developing the screens for that one for the captures. If the menus change appearance, I think the underlying concept remains the same.

-- I browsed the web... It is indeed the same menu page as the one I mentioned yesterday... The problem is finding it... It's the same as "Customize the Ribbon" ...

The starting point is File

To find out how outgoing emails are encoded, go to --> File --> Options --> Advanced and scroll down to ==> International options. Look for the option "Preferred encoding for outgoing messages."

Phew, I found and replaced "Western Alphabet Windows" for "ISO Western alphabet"
All that's left is to wait until I need to make a bulk send with the same addresses, which shouldn't take long, and I'll keep you posted.
A thousand thanks
Best regards

OK, thanks for the feedback... I hope this will solve your problem...

I must say I was unaware of this nuance in group sending...

See you+++