I am using SHA-256 crypt for dovecot. I have added some new users vi postfoxadmin, which is also configured to use she-256 crypt.

looking at the database:

{SHA256-CRYPT}$5$lKfXOxua8j9FIFJt$r4rLmMFHUK/FcJ0c.sp.U4paTeE6Obp0t.mj.6eJQx9 # works {SHA256-CRYPT}$5$Gy.zyFNgYHgSsvmh$C/8Fv47Rjij6S73SwkfhCTwuqGgsmiRCjke6blbt1YD # does not work

(I changed some random character in each line, but didn't change the length)

Jun 12 12:43:09 mail dovecot: auth: Debug: policy(kremels,73.14.161.160,<0VjtyCSLluJJDqGg>): Policy check action is continue Jun 12 12:43:09 mail dovecot: auth-worker(57297): Debug: sql(kremels,73.14.161.160,<0VjtyCSLluJJDqGg>): query: select password FROM mailbox where username ='kremels' Jun 12 12:43:14 mail dovecot: auth: Debug: client passdb out: FAIL#0111#011user=kremel