diff --git a/src/doveadm/doveadm-mail.c b/src/doveadm/doveadm-mail.c
index 54fcca1ccb..4abdb9a132 100644
--- a/src/doveadm/doveadm-mail.c
+++ b/src/doveadm/doveadm-mail.c
@@ -84,6 +84,8 @@ void doveadm_mail_failed_error(struct doveadm_mail_cmd_context *ctx,
 	case MAIL_ERROR_LIMIT:
 		exit_code = DOVEADM_EX_NOTPOSSIBLE;
 		break;
+	case MAIL_ERROR_LOOKUP_ABORTED:
+		break;
 	}
 	/* tempfail overrides all other exit codes, otherwise use whatever
 	   error happened first */
diff --git a/src/imap/imap-commands-util.c b/src/imap/imap-commands-util.c
index d724077231..39dfb5ae70 100644
--- a/src/imap/imap-commands-util.c
+++ b/src/imap/imap-commands-util.c
@@ -141,6 +141,7 @@ imap_get_error_string(struct client_command_context *cmd,
 	case MAIL_ERROR_NONE:
 		break;
 	case MAIL_ERROR_TEMP:
+	case MAIL_ERROR_LOOKUP_ABORTED: /* BUG: shouldn't be visible here */
 		resp_code = IMAP_RESP_CODE_SERVERBUG;
 		break;
 	case MAIL_ERROR_NOTPOSSIBLE:
diff --git a/src/lib-storage/index/index-mailbox-size.c b/src/lib-storage/index/index-mailbox-size.c
index 09e9181ae7..c365954b65 100644
--- a/src/lib-storage/index/index-mailbox-size.c
+++ b/src/lib-storage/index/index-mailbox-size.c
@@ -331,7 +331,7 @@ index_mailbox_vsize_hdr_add_missing(struct mailbox_vsize_update *update,
 		}
 		ret = mail_get_virtual_size(mail, &vsize);
 		if (ret < 0 &&
-		    mailbox_get_last_mail_error(update->box) == MAIL_ERROR_NOTPOSSIBLE) {
+		    mailbox_get_last_mail_error(update->box) == MAIL_ERROR_LOOKUP_ABORTED) {
 			/* abort and finish on background */
 			i_assert(mails_left == 0);
 
diff --git a/src/lib-storage/index/index-search.c b/src/lib-storage/index/index-search.c
index cfb52170cc..8eab25e04b 100644
--- a/src/lib-storage/index/index-search.c
+++ b/src/lib-storage/index/index-search.c
@@ -82,8 +82,8 @@ static void search_cur_mail_failed(struct index_search_context *ctx)
 	case MAIL_ERROR_EXPUNGED:
 		ctx->mail_ctx.seen_lost_data = TRUE;
 		break;
-	case MAIL_ERROR_NOTPOSSIBLE:
-		/* lookup_abort hit */
+	case MAIL_ERROR_LOOKUP_ABORTED:
+		/* expected failure */
 		break;
 	default:
 		search_set_failed(ctx);
diff --git a/src/lib-storage/index/index-sort.c b/src/lib-storage/index/index-sort.c
index 2f0df42887..a7cae3b216 100644
--- a/src/lib-storage/index/index-sort.c
+++ b/src/lib-storage/index/index-sort.c
@@ -43,7 +43,7 @@ index_sort_program_set_mail_failed(struct mail_search_sort_program *program,
 	switch (mailbox_get_last_mail_error(mail->box)) {
 	case MAIL_ERROR_EXPUNGED:
 		break;
-	case MAIL_ERROR_NOTPOSSIBLE:
+	case MAIL_ERROR_LOOKUP_ABORTED:
 		/* just change the error message */
 		mail_storage_set_error(program->t->box->storage, MAIL_ERROR_LIMIT,
 			"Requested sort would have taken too long.");
diff --git a/src/lib-storage/mail-error.h b/src/lib-storage/mail-error.h
index 276d2079b7..81c05d64ee 100644
--- a/src/lib-storage/mail-error.h
+++ b/src/lib-storage/mail-error.h
@@ -51,6 +51,9 @@ enum mail_error {
 	MAIL_ERROR_INVALIDDATA,
 	/* Operation ran against some kind of a limit. */
 	MAIL_ERROR_LIMIT,
+	/* Operation couldn't be finished as efficiently as required by
+	   mail.lookup_abort. */
+	MAIL_ERROR_LOOKUP_ABORTED,
 
 	/* FIXME: Obsolete - remove in v2.3 */
 	MAIL_ERROR_NOSPACE = MAIL_ERROR_NOQUOTA
diff --git a/src/lib-storage/mail.c b/src/lib-storage/mail.c
index da40b2e041..bbb7030de5 100644
--- a/src/lib-storage/mail.c
+++ b/src/lib-storage/mail.c
@@ -247,7 +247,7 @@ int mail_get_header_stream(struct mail *mail,
 
 void mail_set_aborted(struct mail *mail)
 {
-	mail_storage_set_error(mail->box->storage, MAIL_ERROR_NOTPOSSIBLE,
+	mail_storage_set_error(mail->box->storage, MAIL_ERROR_LOOKUP_ABORTED,
 			       "Mail field not cached");
 }
 
diff --git a/src/pop3/pop3-client.c b/src/pop3/pop3-client.c
index a1585fa1ec..5772249ad3 100644
--- a/src/pop3/pop3-client.c
+++ b/src/pop3/pop3-client.c
@@ -97,7 +97,7 @@ pop3_mail_get_size(struct client *client, struct mail *mail, uoff_t *size_r)
 	if (ret == 0)
 		return 0;
 
-	if (mailbox_get_last_mail_error(mail->box) != MAIL_ERROR_NOTPOSSIBLE)
+	if (mailbox_get_last_mail_error(mail->box) != MAIL_ERROR_LOOKUP_ABORTED)
 		return -1;
 
 	/* virtual size not available with a fast lookup.
@@ -108,7 +108,7 @@ pop3_mail_get_size(struct client *client, struct mail *mail, uoff_t *size_r)
 	if (ret == 0)
 		return 0;
 
-	if (mailbox_get_last_mail_error(mail->box) != MAIL_ERROR_NOTPOSSIBLE)
+	if (mailbox_get_last_mail_error(mail->box) != MAIL_ERROR_LOOKUP_ABORTED)
 		return -1;
 
 	/* no way to quickly get the size. fallback to doing a slow virtual