diff --git a/container/shim/src/modules/registration.js b/container/shim/src/modules/registration.js
index 9950230d..3dfe8c62 100644
--- a/container/shim/src/modules/registration.js
+++ b/container/shim/src/modules/registration.js
@@ -51,7 +51,7 @@ export async function register(initial = false) {
     preregisterResponse = await sendPreRegisterRequest(postOptions({ nodeId: NODE_ID }));
   }
 
-  if (preregisterResponse.filesToPurge) {
+  if (preregisterResponse?.filesToPurge) {
     debug("Purging %d files", preregisterResponse.filesToPurge.length);
     for (const file of preregisterResponse.filesToPurge) {
       await purgeCacheFile(file);