diff --git a/ts/SignalProtocolStore.ts b/ts/SignalProtocolStore.ts
index c9c507b79..45a8284fe 100644
--- a/ts/SignalProtocolStore.ts
+++ b/ts/SignalProtocolStore.ts
@@ -1095,7 +1095,7 @@ export class SignalProtocolStore extends EventsMixin {
         throw new Error('getOpenDevices: this.sessions not yet cached!');
       }
       if (identifiers.length === 0) {
-        throw new Error('getOpenDevices: No identifiers provided!');
+        return { devices: [], emptyIdentifiers: [] };
       }
 
       try {
diff --git a/ts/jobs/helpers/sendDeleteForEveryone.ts b/ts/jobs/helpers/sendDeleteForEveryone.ts
index 37b62337a..a1fb1dd7a 100644
--- a/ts/jobs/helpers/sendDeleteForEveryone.ts
+++ b/ts/jobs/helpers/sendDeleteForEveryone.ts
@@ -123,6 +123,12 @@ export async function sendDeleteForEveryone(
             );
             return;
           }
+          if (conversation.isBlocked()) {
+            log.info(
+              `conversation ${conversation.idForLogging()} is blocked; refusing to send`
+            );
+            return;
+          }
 
           await wrapWithSyncMessageSend({
             conversation,
diff --git a/ts/jobs/helpers/sendDirectExpirationTimerUpdate.ts b/ts/jobs/helpers/sendDirectExpirationTimerUpdate.ts
index e242f01d1..efd2d5921 100644
--- a/ts/jobs/helpers/sendDirectExpirationTimerUpdate.ts
+++ b/ts/jobs/helpers/sendDirectExpirationTimerUpdate.ts
@@ -115,6 +115,12 @@ export async function sendDirectExpirationTimerUpdate(
         );
         return;
       }
+      if (conversation.isBlocked()) {
+        log.info(
+          `conversation ${conversation.idForLogging()} is blocked; refusing to send`
+        );
+        return;
+      }
 
       await wrapWithSyncMessageSend({
         conversation,
diff --git a/ts/jobs/helpers/sendNormalMessage.ts b/ts/jobs/helpers/sendNormalMessage.ts
index b5dd138ee..ea2920143 100644
--- a/ts/jobs/helpers/sendNormalMessage.ts
+++ b/ts/jobs/helpers/sendNormalMessage.ts
@@ -229,6 +229,13 @@ export async function sendNormalMessage(
           ]);
           return;
         }
+        if (conversation.isBlocked()) {
+          log.info(
+            `conversation ${conversation.idForLogging()} is blocked; refusing to send`
+          );
+          markMessageFailed(message, [new Error('Contact is blocked')]);
+          return;
+        }
 
         log.info('sending direct message');
         innerPromise = window.textsecure.messaging.sendMessageToIdentifier({
diff --git a/ts/jobs/helpers/sendProfileKey.ts b/ts/jobs/helpers/sendProfileKey.ts
index 8d429dcbc..3e7cb1b07 100644
--- a/ts/jobs/helpers/sendProfileKey.ts
+++ b/ts/jobs/helpers/sendProfileKey.ts
@@ -97,6 +97,12 @@ export async function sendProfileKey(
       );
       return;
     }
+    if (conversation.isBlocked()) {
+      log.info(
+        `conversation ${conversation.idForLogging()} is blocked; refusing to send`
+      );
+      return;
+    }
 
     const proto = await window.textsecure.messaging.getContentMessage({
       flags: Proto.DataMessage.Flags.PROFILE_KEY_UPDATE,
diff --git a/ts/jobs/helpers/sendReaction.ts b/ts/jobs/helpers/sendReaction.ts
index cbfec342e..49097192f 100644
--- a/ts/jobs/helpers/sendReaction.ts
+++ b/ts/jobs/helpers/sendReaction.ts
@@ -196,6 +196,13 @@ export async function sendReaction(
           markReactionFailed(message, pendingReaction);
           return;
         }
+        if (conversation.isBlocked()) {
+          log.info(
+            `conversation ${conversation.idForLogging()} is blocked; refusing to send`
+          );
+          markReactionFailed(message, pendingReaction);
+          return;
+        }
 
         log.info('sending direct reaction message');
         promise = window.textsecure.messaging.sendMessageToIdentifier({
diff --git a/ts/jobs/singleProtoJobQueue.ts b/ts/jobs/singleProtoJobQueue.ts
index 8a0d8bfae..f08b6897c 100644
--- a/ts/jobs/singleProtoJobQueue.ts
+++ b/ts/jobs/singleProtoJobQueue.ts
@@ -90,6 +90,12 @@ export class SingleProtoJobQueue extends JobQueue<SingleProtoJobData> {
       );
       return;
     }
+    if (conversation.isBlocked()) {
+      log.info(
+        `conversation ${conversation.idForLogging()} is blocked; refusing to send`
+      );
+      return;
+    }
 
     const proto = Proto.Content.decode(Bytes.fromBase64(protoBase64));
     const options = await getSendOptions(conversation.attributes, {
diff --git a/ts/util/getConversationMembers.ts b/ts/util/getConversationMembers.ts
index 536444d3d..efb1f7ad9 100644
--- a/ts/util/getConversationMembers.ts
+++ b/ts/util/getConversationMembers.ts
@@ -27,8 +27,11 @@ export function getConversationMembers(
       members.map(member => {
         const conversation = window.ConversationController.get(member.uuid);
 
-        // In groups we won't sent to contacts we believe are unregistered
-        if (conversation && conversation.isUnregistered()) {
+        // In groups we won't sent to blocked contacts or those we think are unregistered
+        if (
+          conversation &&
+          (conversation.isUnregistered() || conversation.isBlocked())
+        ) {
           return null;
         }
 
@@ -42,8 +45,11 @@ export function getConversationMembers(
       conversationAttrs.members.map(id => {
         const conversation = window.ConversationController.get(id);
 
-        // In groups we won't send to contacts we believe are unregistered
-        if (conversation && conversation.isUnregistered()) {
+        // In groups we won't sent to blocked contacts or those we think are unregistered
+        if (
+          conversation &&
+          (conversation.isUnregistered() || conversation.isBlocked())
+        ) {
           return null;
         }
 
diff --git a/ts/util/sendReceipts.ts b/ts/util/sendReceipts.ts
index eec9b2fbd..f455e99a9 100644
--- a/ts/util/sendReceipts.ts
+++ b/ts/util/sendReceipts.ts
@@ -103,6 +103,12 @@ export async function sendReceipts({
         );
         return;
       }
+      if (sender.isBlocked()) {
+        log.info(
+          `conversation ${sender.idForLogging()} is blocked; refusing to send`
+        );
+        return;
+      }
 
       const sendOptions = await getSendOptions(sender.attributes);