>>> "ESF" == Eric S Fraga <e.fraga@ucl.ac.uk> writes:

> On Monday, 30 Mar 2020 at 09:22, Uwe Brauer wrote:
>> From time to time I receive message, perfectly displayed in thunderbird,
>> but in gnus I only see:
>> ,----
>> | 
>> | From: Joe Doe
>> | Subject: Algunos videos y diapositivas actualizadas
>> | To: Uwe Brauer <oub@mat.ucm.es>
>> | Date: Mon, 30 Mar 2020 08:07:26 +0200 (4 minutes, 45 seconds ago)
>> | Attachments: [3. application/octet-stream]... [5. application/pdf]... [7. text/plain]...
>> | 
>> | [3. application/octet-stream]...
>> | 
>> | [5. application/pdf]...
>> `----

> The problem is likely that the sender (or sender's MUA) did not specify
> a proper mime type for the 3rd component.  You could tab to it and type
> t to select the type of application/attachment.  gnus should be able to
> display it then.

That was very useful, thank you.