Thank you very much! This works. On Wednesday, December 2, 2020, 11:44:24 AM CST, Zenithal <i at zenithal.me> wrote: > '=?utf-8?Q?efficient=5Fkkmeans.pdf?=' This is RFC2047-encoded MIME parameters. You may add set rfc2047_parameters = yes in your muttrc. -- GPG Fingerprint: 1127F188280AE3123619332987E17EEF9B18B6C9