> On 20/01/2022 23:44 mauric at gmx.ch wrote: > > > it’s possible to update only sieve 0.5.17, on existing Debian Buster Dovecot installation? > Running now -> sieve: Pigeonhole version 0.5.4 There are sone sieve versions that work with older dovecot versions, but the safest option is to run same version: 2.3.x = 0.5.x Aki