I tried evaluating find-file-name-handler as suggested and it  
returns nil. I suspect it is due to OneDrive (and now also  
Nextcloud's) virtual files, which live online until requested. Somehow  
opening the file does not trigger the required download.

Juanjo

Lars Ingebrigtsen <larsi@gnus.org> escribió:

> Juan José García-Ripoll <juanjose.garcia.ripoll@csic.es> writes:
>
>> The file is living in OneDrive in Windows 10/11. I will try with other
>> files in the same file system, but it has hit me hard this week, which
>> I am in remote mode.
>
> As Eli says, buffer-file-name apparently being nil in this case, and
> that's very odd.
>
> Could there be a special file name handler for OneDrive that's doing
> something odd?
>
> What does
>
> M-: (find-file-name-handler  
> "~/OneDrive/Mail/archive/Archives-2017.mbox" 'insert-file-contents)  
> RET
> say?
   Juan José García Ripoll

Instituto de Física Fundamental, CSIC
Calle Serrano 113b, Madrid 28006, Spain
Phone: (+34) 915616800 (dial 943107 when hearing the voice)
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