diff --git a/res/values/strings.xml b/res/values/strings.xml
index f91c9da60..9abcba31c 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -600,7 +600,7 @@
     <string name="pref_background_btn_default">Use Default Image</string>
     <string name="pref_background_btn_gallery">Select From Gallery</string>
     <string name="pref_imap_folder_handling">IMAP Folder Handling</string>
-    <string name="pref_imap_folder_warn_disable_defaults">If you disable this option, make sure, your server and your other clients are configured accordingly.\n\nOtherwise things may not work at all.</string>
+    <string name="pref_imap_folder_warn_disable_defaults">If you change this option, make sure, your server and your other clients are configured accordingly.\n\nOtherwise things may not work at all.</string>
     <string name="pref_watch_inbox_folder">Watch Inbox Folder</string>
     <string name="pref_watch_sent_folder">Watch Sent Folder</string>
     <string name="pref_watch_mvbox_folder">Watch DeltaChat Folder</string>
diff --git a/src/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java b/src/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java
index c650626bf..55476367f 100644
--- a/src/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java
+++ b/src/org/thoughtcrime/securesms/preferences/AdvancedPreferenceFragment.java
@@ -92,11 +92,25 @@ public class AdvancedPreferenceFragment extends ListSummaryPreferenceFragment
 
     onlyFetchMvboxCheckbox = this.findPreference("pref_only_fetch_mvbox");
     onlyFetchMvboxCheckbox.setOnPreferenceChangeListener(((preference, newValue) -> {
-      boolean enabled = (Boolean) newValue;
-      DcHelper.getAccounts(getContext()).stopIo();
-      dcContext.setConfigInt(CONFIG_ONLY_FETCH_MVBOX, enabled? 1 : 0);
-      DcHelper.getAccounts(getContext()).startIo();
-      return true;
+      final boolean enabled = (Boolean) newValue;
+      if (enabled) {
+        new AlertDialog.Builder(getContext())
+                .setMessage(R.string.pref_imap_folder_warn_disable_defaults)
+                .setPositiveButton(R.string.ok, (dialogInterface, i) -> {
+                  DcHelper.getAccounts(getContext()).stopIo();
+                  dcContext.setConfigInt(CONFIG_ONLY_FETCH_MVBOX, 1);
+                  ((CheckBoxPreference)preference).setChecked(true);
+                  DcHelper.getAccounts(getContext()).startIo();
+                })
+                .setNegativeButton(R.string.cancel, null)
+                .show();
+        return false;
+      } else {
+        DcHelper.getAccounts(getContext()).stopIo();
+        dcContext.setConfigInt(CONFIG_ONLY_FETCH_MVBOX, 0);
+        DcHelper.getAccounts(getContext()).startIo();
+        return true;
+      }
     }));
 
     Preference manageKeys = this.findPreference("pref_manage_keys");