diff --git a/install_postfix_advanced.sh b/install_postfix_advanced.sh
index d9fee7c..b265da4 100755
--- a/install_postfix_advanced.sh
+++ b/install_postfix_advanced.sh
@@ -1539,6 +1539,7 @@ cat <<EOF >> /etc/postfix/main.cf
 ## -
 ## - using dovecot lda
 ## -    virtual_transport = dovecot
+## -    dovecot_destination_recipient_limit = 1
 ## -
 ## - using dovecot's lmtp service
 ## -    virtual_transport = lmtp:unix:private/dovecot-lmtp
diff --git a/install_update_dovecot.sh b/install_update_dovecot.sh
index 91ed69b..00fd51c 100755
--- a/install_update_dovecot.sh
+++ b/install_update_dovecot.sh
@@ -2797,45 +2797,100 @@ else
 fi
 
 
-#if $_new ; then
-#
-#   ## - /etc/postfix/main.cf
-#   ## -
-#   ## - comment in:
-#   ## -    #virtual_transport = dovecot
-#   ## -
-#   ## - change:
-#   ## -    smtpd_sasl_auth_enable = yes
-#   ## -    smtpd_sasl_type = dovecot
-#   ## -    smtpd_sasl_path = private/dovecot-auth
-#   ## -    virtual_transport = lmtp:unix:private/dovecot-lmtp
-#   _failed=false
-#   echononl "\tAdjust /etc/postfix/main.cf"
-#   perl -i -n -p -e "s#^(\s*)(smtpd_sasl_auth_enable\ *=.*)#smtpd_sasl_auth_enable = yes#" \
-#      /etc/postfix/main.cf || _failed=true
-#   #perl -i -n -p -e "s#^(\s*)(smtpd_sasl_type\ *=.*)#\1\#\2\n\1smtpd_sasl_type = dovecot#" \
-#   perl -i -n -p -e "s#^(\s*)(smtpd_sasl_type\ *=.*)#smtpd_sasl_type = dovecot#" \
-#      /etc/postfix/main.cf || _failed=true
-#   #perl -i -n -p -e "s#^(\s*)(smtpd_sasl_path\ *=.*)#\1\#\2\n\1smtpd_sasl_path = private/dovecot-auth#" \
-#   #   /etc/postfix/main.cf || _failed=true
-#   perl -i -n -p -e "s#^(\s*)(smtpd_sasl_path\ *=.*)#smtpd_sasl_path = private/dovecot-auth#" \
-#      /etc/postfix/main.cf || _failed=true
-#
-#
-#
-#   #perl -i -n -p -e "s#^(\s*)(virtual_transport\ *=.*)#\1\#\2\n\1virtual_transport = lmtp:unix:private/dovecot-lmtp#" \
-#   #   /etc/postfix/main.cf || _failed=true
-#   perl -i -n -p -e "s#^(\s*)(virtual_transport\ *=.*)#virtual_transport = lmtp:unix:private/dovecot-lmtp#" \
-#      /etc/postfix/main.cf || _failed=true
-#   perl -i-n -p -e "s#^(\s*)(dovecot_destination_recipient_limit.*)#\1\#\2#" /etc/postfix/main.cf  || _failed=true
-#   if ! $_failed ; then
-#      echo -e "$rc_done"
-#   else
-#      echo -e "$rc_failed"
-#      fatal "Adjusting /etc/postfix/main.cf failed"
-#   fi
-#
-#fi
+# - /etc/postfix/main.cf
+# -
+# - comment in:
+# -    #virtual_transport = dovecot
+# -    #dovecot_destination_recipient_limit = ..
+# -
+# - change:
+# -    smtpd_sasl_auth_enable = yes
+# -    smtpd_sasl_type = dovecot
+# -    smtpd_sasl_path = private/dovecot-auth
+# -    virtual_transport = lmtp:unix:private/dovecot-lmtp
+var="smtpd_sasl_auth_enable"
+val="yes"
+echononl "\t${postfix_main_cf}: adjust '${val}'.."
+if ! $(grep -E -q "^\s*${var}\s*=\s*${val}" ${postfix_main_cf} 2> /dev/null) ; then
+   perl -i -n -p -e "s#^(\s*)(smtpd_sasl_type\ *=.*)#smtpd_sasl_type = dovecot#" \
+      /etc/postfix/main.cf > $log_file 2>&1
+   if [[ $? -eq 0 ]]; then
+      echo_ok
+      changed=true
+   else
+      echo_failed
+      error "$(cat "$log_file")"
+   fi
+else
+   echo_skipped
+fi
+
+var="smtpd_sasl_type"
+val="dovecot"
+echononl "\t${postfix_main_cf}: adjust '${val}'.."
+if ! $(grep -E -q "^\s*${var}\s*=\s*${val}" ${postfix_main_cf} 2> /dev/null) ; then
+   perl -i -n -p -e "s#^(\s*)(smtpd_sasl_type\ *=.*)#smtpd_sasl_type = dovecot#" \
+      /etc/postfix/main.cf > $log_file 2>&1
+   if [[ $? -eq 0 ]]; then
+      echo_ok
+      changed=true
+   else
+      echo_failed
+      error "$(cat "$log_file")"
+   fi
+else
+   echo_skipped
+fi
+
+var="smtpd_sasl_path"
+val="private/dovecot-auth"
+echononl "\t${postfix_main_cf}: adjust '${val}'.."
+if ! $(grep -E -q "^\s*${var}\s*=\s*${val}" ${postfix_main_cf} 2> /dev/null) ; then
+   perl -i -n -p -e "s#^(\s*)(smtpd_sasl_type\ *=.*)#smtpd_sasl_type = dovecot#" \
+      /etc/postfix/main.cf > $log_file 2>&1
+   if [[ $? -eq 0 ]]; then
+      echo_ok
+      changed=true
+   else
+      echo_failed
+      error "$(cat "$log_file")"
+   fi
+else
+   echo_skipped
+fi
+
+var="virtual_transport"
+val="lmtp:unix:private/dovecot-lmtp"
+echononl "\t${postfix_main_cf}: adjust '${val}'.."
+if ! $(grep -E -q "^\s*${var}\s*=\s*${val}" ${postfix_main_cf} 2> /dev/null) ; then
+   perl -i -n -p -e "s#^(\s*)(smtpd_sasl_type\ *=.*)#smtpd_sasl_type = dovecot#" \
+      /etc/postfix/main.cf > $log_file 2>&1
+   if [[ $? -eq 0 ]]; then
+      echo_ok
+   else
+      echo_failed
+      changed=true
+      error "$(cat "$log_file")"
+   fi
+else
+   echo_skipped
+fi
+
+
+echononl "\tComment variable 'dovecot_destination_recipient_limit'.."
+if $(grep -E -q "^\s*dovecot_destination_recipient_limit" ${postfix_main_cf} 2> /dev/null) ; then
+   perl -i-n -p -e "s/^(\s*)(dovecot_destination_recipient_limit.*)/\1\#\2/" /etc/postfix/main.cf > $log_file 2>&1
+   if [[ $? -eq 0 ]]; then
+      echo_ok
+      changed=true
+   else
+      echo_failed
+      error "$(cat "$log_file")"
+   fi
+else
+   echo_skipped
+fi
+
 
 
 ## -----------------