I've just set up dovecot-2.3.20-1.fc37.x86_64 on fedora37 and unable to receive mail. The main config was copied over from another dovecot system on fedora37 with virtually identical settings, including the same SSL cert. I've also tried to just migrate the important stuff and otherwise leave the defaults, but I'm having the same problem.

imap(bcc-user)<2977522><rappeBf6vLZEw8Eq>: Debug: Loading modules from directory: /usr/lib64/dovecot

imap(bcc-user)<2977522><rappeBf6vLZEw8Eq>: Debug: Module loaded: /usr/lib64/dovecot/lib20_listescape_plugin.so

imap(bcc-user)<2977522><rappeBf6vLZEw8Eq>: Debug: Effective uid=1001, gid=1001, home=/home/bcc-user

imap(bcc-user)<2977522><rappeBf6vLZEw8Eq>: Debug: open(/proc/self/io) failed: Permission denied

imap(bcc-user)<2977522><rappeBf6vLZEw8Eq>: Debug: Namespace inbox: type=private, prefix=, sep=, inbox=yes, hidden=no, list=yes, subscriptions=yes location=mbox:~/mail:INBOX=/var/spool/mail/bcc-user

imap(bcc-user)<2977522><rappeBf6vLZEw8Eq>: Debug: fs: root=/home/bcc-user/mail, index=, indexpvt=, control=, inbox=/var/spool/mail/bcc-user, alt=

imap(bcc-user)<2977522><rappeBf6vLZEw8Eq>: Debug: Mailbox Trash: Mailbox opened

I've set the /var/spool/mail/bcc-user permissions to 600, bcc-user:mail. The /home/bcc-user directory is 611, bcc-user:bcc-user.

Here is my doveconf -n:

# 2.3.20 (80a5ac675d): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.5.20 (149edcf2)
# OS: Linux 6.1.15-200.fc37.x86_64 x86_64 Fedora release 37 (Thirty Seven)
auth_debug = yes
auth_verbose = yes
mail_debug = yes
mail_gid = mail
mail_home = mail/
mail_location = mbox:~/mail:INBOX=/var/spool/mail/%u
mail_max_userip_connections = 500
mail_plugins = " listescape"
mail_privileged_group = mail
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext
mbox_write_locks = fcntl
namespace inbox {
  inbox = yes
  location =
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix =
}
passdb {
  driver = pam
}
protocols = imap
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0660
    user = postfix
  }
}
service imap-login {
  inet_listener imap {
    port = 0
  }
  inet_listener imaps {
    port = 993
  }
  process_min_avail = 6
  service_count = 0
  vsz_limit = 512 M
}
ssl_cert = </etc/letsencrypt/fullchain.cer
ssl_cipher_list = ALL:!LOW:!EXP:!aNULL:!RC4::!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!SRP:!DSS
ssl_dh = # hidden, use -P to show it
ssl_key = # hidden, use -P to show it
ssl_prefer_server_ciphers = yes
userdb {
  driver = passwd
}
verbose_ssl = yes

Any ideas greatly appreciated. I was very surprised to be having problems after having done this so many times before.