diff --git a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxDownloadWorker.java b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxDownloadWorker.java
index 2994dbbc4..a70f18d69 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxDownloadWorker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/ContactMailboxDownloadWorker.java
@@ -90,7 +90,7 @@ class ContactMailboxDownloadWorker implements MailboxWorker,
 		LOG.info("Started");
 		synchronized (lock) {
 			// Don't allow the worker to be reused
-			if (state != State.CREATED) throw new IllegalStateException();
+			if (state != State.CREATED) return;
 			state = State.CONNECTIVITY_CHECK;
 		}
 		// Avoid leaking observer in case destroy() is called concurrently
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUploadWorker.java b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUploadWorker.java
index e0f3496a1..5c6462c6d 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUploadWorker.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/mailbox/MailboxUploadWorker.java
@@ -147,7 +147,7 @@ class MailboxUploadWorker implements MailboxWorker, ConnectivityObserver,
 		LOG.info("Started");
 		synchronized (lock) {
 			// Don't allow the worker to be reused
-			if (state != State.CREATED) throw new IllegalStateException();
+			if (state != State.CREATED) return;
 			state = State.CHECKING_FOR_DATA;
 		}
 		ioExecutor.execute(this::checkForDataToSend);