diff --git a/src/bin/pg_dump/pg_backup_archiver.c b/src/bin/pg_dump/pg_backup_archiver.c
index c57799e84f..e091d87a52 100644
--- a/src/bin/pg_dump/pg_backup_archiver.c
+++ b/src/bin/pg_dump/pg_backup_archiver.c
@@ -3265,6 +3265,12 @@ restore_toc_entries_parallel(ArchiveHandle *AH)
 	if (AH->version < K_VERS_1_8)
 		die_horribly(AH, modulename, "parallel restore is not supported with archives made by pre-8.0 pg_dump\n");
 
+	/*
+	 * It's also not gonna work if we can't reopen the input file, so let's
+	 * try that immediately.
+	 */
+	(AH->ReopenPtr) (AH);
+
 	slots = (ParallelSlot *) calloc(sizeof(ParallelSlot), n_slots);
 
 	/* Adjust dependency information */
diff --git a/src/bin/pg_dump/pg_backup_custom.c b/src/bin/pg_dump/pg_backup_custom.c
index 01d5e37999..9224d7bbe2 100644
--- a/src/bin/pg_dump/pg_backup_custom.c
+++ b/src/bin/pg_dump/pg_backup_custom.c
@@ -735,10 +735,15 @@ _ReopenArchive(ArchiveHandle *AH)
 
 	if (AH->mode == archModeWrite)
 		die_horribly(AH, modulename, "can only reopen input archives\n");
+
+	/*
+	 * These two cases are user-facing errors since they represent unsupported
+	 * (but not invalid) use-cases.  Word the error messages appropriately.
+	 */
 	if (AH->fSpec == NULL || strcmp(AH->fSpec, "") == 0)
-		die_horribly(AH, modulename, "cannot reopen stdin\n");
+		die_horribly(AH, modulename, "parallel restore from stdin is not supported\n");
 	if (!ctx->hasSeek)
-		die_horribly(AH, modulename, "cannot reopen non-seekable file\n");
+		die_horribly(AH, modulename, "parallel restore from non-seekable file is not supported\n");
 
 	errno = 0;
 	tpos = ftello(AH->FH);