diff --git a/lib/backend_sgx.rb b/lib/backend_sgx.rb
index 743105bb0080a416082d27c2f3f94f5626a20fcd..c0ef5557d4b359a986fafb3f4efd8424cafdeeb9 100644
--- a/lib/backend_sgx.rb
+++ b/lib/backend_sgx.rb
@@ -9,6 +9,8 @@ require_relative "not_loaded"
 require_relative "form_to_h"
 
 class BackendSgx
+	class CanceledError < StandardError; end
+
 	using FormToH
 
 	value_semantics do
diff --git a/sgx_jmp.rb b/sgx_jmp.rb
index ca024c70c1e1acd59cac4f1711303d3bf8c0ef1d..45e0136ad92c5dafbe3528da0a3a1e56733ba01c 100644
--- a/sgx_jmp.rb
+++ b/sgx_jmp.rb
@@ -898,8 +898,10 @@ Command.new(
 			raise "PIN and confirm PIN must match." unless pin == confirm_pin
 
 			customer.set_port_out_pin(pin)
-		}.then do
+		}.then {
 			Command.finish("Your port-out PIN has been set.")
+		}.catch_only(BackendSgx::CanceledError) do |e|
+			Command.finish(e.message, status: :canceled)
 		end
 	end
 }.register(self).then(&CommandList.method(:register))