diff --git a/app/src/main/java/com/zulip/android/activities/LoginActivity.java b/app/src/main/java/com/zulip/android/activities/LoginActivity.java
index 57e33f748..6bdc07461 100644
--- a/app/src/main/java/com/zulip/android/activities/LoginActivity.java
+++ b/app/src/main/java/com/zulip/android/activities/LoginActivity.java
@@ -271,6 +271,7 @@ private boolean isUrlValid(String url) {
 
     private void showBackends(String httpScheme, String serverURL) {
         commonProgressDialog.showWithMessage(getString(R.string.connecting_to_server));
+        commonProgressDialog.setCancelable(false);
         // if server url does not end with "/", then append it
         if (!serverURL.endsWith("/")) {
             serverURL = serverURL + "/";
@@ -498,6 +499,7 @@ public void onClick(View v) {
         switch (v.getId()) {
             case R.id.google_sign_in_button:
                 commonProgressDialog.showWithMessage(getString(R.string.signing_in));
+                commonProgressDialog.setCancelable(false);
                 setupGoogleSignIn();
                 break;
             case R.id.zulip_login:
@@ -505,6 +507,7 @@ public void onClick(View v) {
                     return;
                 }
                 commonProgressDialog.showWithMessage(getString(R.string.signing_in));
+                commonProgressDialog.setCancelable(false);
                 String username = mUserName.getText().toString();
                 String password = mPassword.getText().toString();
                 getServices()
@@ -559,6 +562,7 @@ public void onFailure(Call<LoginResponse> call, Throwable t) {
             case R.id.local_server_button:
                 if (!isInputValidForDevAuth()) return;
                 commonProgressDialog.showWithMessage(getString(R.string.signing_in));
+                commonProgressDialog.setCancelable(false);
                 AsyncDevGetEmails asyncDevGetEmails = new AsyncDevGetEmails(LoginActivity.this);
                 asyncDevGetEmails.setCallback(new ZulipAsyncPushTask.AsyncTaskCompleteListener() {
                     @Override
diff --git a/app/src/main/java/com/zulip/android/activities/ZulipActivity.java b/app/src/main/java/com/zulip/android/activities/ZulipActivity.java
index 71ed7b068..440f22781 100644
--- a/app/src/main/java/com/zulip/android/activities/ZulipActivity.java
+++ b/app/src/main/java/com/zulip/android/activities/ZulipActivity.java
@@ -22,6 +22,8 @@
 import android.graphics.Bitmap;
 import android.graphics.PorterDuff;
 import android.graphics.drawable.Drawable;
+import android.net.ConnectivityManager;
+import android.net.NetworkInfo;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
@@ -2081,8 +2083,14 @@ public void onClick(
                 break;
             case R.id.refresh:
                 Log.w("menu", "Refreshed manually by user. We shouldn't need this.");
-                commonProgressDialog.showWithMessage(getString(R.string.refreshing));
-                onRefresh();
+                if (!isNetworkAvailable()) {
+                    Toast.makeText(ZulipActivity.this, R.string.toast_no_internet_connection, Toast.LENGTH_SHORT).show();
+                    commonProgressDialog.dismiss();
+                } else {
+                    commonProgressDialog.showWithMessage(getString(R.string.refreshing));
+                    commonProgressDialog.setCancelable(false);
+                    onRefresh();
+                }
                 break;
             case R.id.today:
                 //check user selected Today or One Day Before
@@ -2141,6 +2149,7 @@ private void setNightMode(@AppCompatDelegate.NightMode int nightMode) {
      */
     private void logout() {
         commonProgressDialog.showWithMessage(getString(R.string.logging_out));
+        commonProgressDialog.setCancelable(false);
         this.logged_in = false;
         final String serverUrl = app.getServerHostUri();
 
@@ -2358,4 +2367,11 @@ public MessageListFragment getCurrentMessageList() {
     public enum Flag {
         RESET_DATABASE,
     }
+
+    private boolean isNetworkAvailable() {
+        ConnectivityManager connectivityManager
+                = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
+        NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
+        return activeNetworkInfo != null && activeNetworkInfo.isConnected();
+    }
 }
diff --git a/app/src/main/java/com/zulip/android/util/CommonProgressDialog.java b/app/src/main/java/com/zulip/android/util/CommonProgressDialog.java
index 71e3daf3d..e6da6b04c 100644
--- a/app/src/main/java/com/zulip/android/util/CommonProgressDialog.java
+++ b/app/src/main/java/com/zulip/android/util/CommonProgressDialog.java
@@ -37,4 +37,8 @@ public boolean isShowing() {
     public void setMessage(String message) {
         progressDialog.setMessage(message);
     }
+
+    public void setCancelable(boolean cancelable) {
+        progressDialog.setCancelable(cancelable);
+    }
 }