diff --git a/test/bug.634.t b/test/bug.634.t
index 3b2c8a8e4..9ae10469b 100755
--- a/test/bug.634.t
+++ b/test/bug.634.t
@@ -45,7 +45,7 @@ if (open my $fh, '>', 'bug.rc')
 qx{../src/task rc:bug.rc add Test};
 
 # Result: Attempt to undo add with confirmation=off
-my $output = qx{echo 'n' |../src/task rc.confirmation=off undo};
+my $output = qx{echo 'n' |../src/task rc:bug.rc rc.confirmation=off undo};
 unlike ($output, qr/Are you sure/ms, 'Undo honours confirmation=off.');
 
 # Cleanup.