diff --git a/hooks/__tests__/use-pro-multi-account-mailboxes.test.tsx b/hooks/__tests__/use-pro-multi-account-mailboxes.test.tsx
index 9201eb17e..5b6d9c669 100644
--- a/hooks/__tests__/use-pro-multi-account-mailboxes.test.tsx
+++ b/hooks/__tests__/use-pro-multi-account-mailboxes.test.tsx
@@ -71,6 +71,18 @@ describe('useProMultiAccountMailboxes', () => {
     expect(client('b').getMailboxes).toHaveBeenCalledTimes(2);
   });
 
+  it('tries a login again when its first folder load failed', async () => {
+    vi.spyOn(console, 'error').mockImplementation(() => {});
+    connected(['a', 'b']);
+    client('b').getMailboxes.mockRejectedValueOnce(new Error('offline'));
+    renderHook(() => useProMultiAccountMailboxes());
+    await waitFor(() => expect(client('b').getMailboxes).toHaveBeenCalledTimes(1));
+    await act(async () => { await new Promise((r) => setTimeout(r, 0)); });
+    act(() => connected(['a', 'b', 'c']));
+    await waitFor(() => expect(useEmailStore.getState().accountMailboxes.b).toBeDefined());
+    expect(client('b').getMailboxes).toHaveBeenCalledTimes(2);
+  });
+
   it('stays idle outside the Pro shell', () => {
     useSettingsStore.setState({ proInterface: false } as never);
     connected(['a', 'b']);
diff --git a/hooks/use-pro-multi-account-mailboxes.ts b/hooks/use-pro-multi-account-mailboxes.ts
index c3ffd734a..96f38c954 100644
--- a/hooks/use-pro-multi-account-mailboxes.ts
+++ b/hooks/use-pro-multi-account-mailboxes.ts
@@ -53,7 +53,10 @@ export function useProMultiAccountMailboxes(): void {
       const client = getClientForAccount(id);
       if (!client || loaded.current.get(id) === client) continue;
       loaded.current.set(id, client);
-      void loadAccountMailboxes(client, id);
+      void loadAccountMailboxes(client, id).then((ok) => {
+        // Try a failed login again on the next run, as the identities hook does.
+        if (!ok && loaded.current.get(id) === client) loaded.current.delete(id);
+      });
     }
   }, [proInterface, isEmbedded, connectedSignature, activeAccountId]);
 }
diff --git a/stores/__tests__/email-store-unified-mailbox-cache.test.ts b/stores/__tests__/email-store-unified-mailbox-cache.test.ts
index 6735757ed..0b7959bff 100644
--- a/stores/__tests__/email-store-unified-mailbox-cache.test.ts
+++ b/stores/__tests__/email-store-unified-mailbox-cache.test.ts
@@ -1,5 +1,5 @@
 import { beforeEach, describe, expect, it, vi } from 'vitest';
-import { buildUnifiedAccountClients, invalidateUnifiedMailboxes, useEmailStore } from '../email-store';
+import { buildUnifiedAccountClients, invalidateUnifiedMailboxes, loadAccountMailboxes, useEmailStore } from '../email-store';
 import { useAccountStore } from '../account-store';
 import { useAuthStore } from '../auth-store';
 import type { IJMAPClient } from '@/lib/jmap/client-interface';
@@ -109,6 +109,16 @@ describe('unified scope folder lists', () => {
     expect(useEmailStore.getState().accountMailboxes.a[0].unreadEmails).toBe(4);
   });
 
+  it('publishes a list the Pro shell loaded under the JMAP id too', async () => {
+    const b = fakeClient('b');
+    connect({ b });
+    await loadAccountMailboxes(b as unknown as IJMAPClient, 'b');
+    await buildUnifiedAccountClients();
+    expect(b.getMailboxes).toHaveBeenCalledTimes(1);
+    // Actions on b's mail resolve its folders by JMAP id.
+    expect(useEmailStore.getState().accountMailboxes['jmap-b']?.[0].id).toBe('b-inbox');
+  });
+
   it('retries a login whose fetch failed', async () => {
     const a = fakeClient('a');
     a.getMailboxes.mockRejectedValueOnce(new Error('offline'));
diff --git a/stores/email-store.ts b/stores/email-store.ts
index c91b62655..2c89261ab 100644
--- a/stores/email-store.ts
+++ b/stores/email-store.ts
@@ -1065,15 +1065,17 @@ async function unifiedMailboxesFor(
  * the unified scope uses, so the two never fetch the same list twice and a
  * list already there is not fetched again until that login reports a change.
  */
-export async function loadAccountMailboxes(client: IJMAPClient, accountId: string): Promise<void> {
+export async function loadAccountMailboxes(client: IJMAPClient, accountId: string): Promise<boolean> {
   try {
     const { mailboxes, fresh } = await unifiedMailboxesFor(client, false);
-    if (!fresh && useEmailStore.getState().accountMailboxes[accountId]) return;
+    if (!fresh && useEmailStore.getState().accountMailboxes[accountId]) return true;
     useEmailStore.setState((state) => ({
       accountMailboxes: { ...state.accountMailboxes, [accountId]: mailboxes.slice() },
     }));
+    return true;
   } catch (error) {
     console.error(`Failed to fetch mailboxes for account ${accountId}:`, error);
+    return false;
   }
 }
 
@@ -1110,6 +1112,10 @@ export async function buildUnifiedAccountClients(
     // Skip the account on mailbox fetch failure.
     if (result.status !== 'fulfilled' || !result.value) continue;
     const { a, c, mailboxes, fresh } = result.value;
+    // A reused list never overwrites a live one, but fills a key nothing has published yet.
+    const publish = (key: string, list: Mailbox[]) => {
+      if (fresh || !useEmailStore.getState().accountMailboxes[key]) fetchedMailboxes[key] = list;
+    };
     try {
       const ownMailboxes = includeGroup
         ? mailboxes.filter((m) => !m.isShared)
@@ -1120,12 +1126,10 @@ export async function buildUnifiedAccountClients(
       // resolution branch-free against shared sources.
       const primaryJmapId = c.getAccountId();
       built.push({ accountId: a.id, accountLabel: a.label || a.email, client: c, mailboxes: ownMailboxes, clientAccountId: a.id, jmapAccountId: primaryJmapId, isShared: false, crossIncludedMailboxIds: resolveCrossIncludedMailboxIds(a.id, ownMailboxes) });
-      if (fresh) {
-        fetchedMailboxes[a.id] = ownMailboxes;
-        // Also cache under the JMAP id so `accountMailboxes[email.sourceAccountId]`
-        // resolves uniformly for personal and shared sources alike.
-        fetchedMailboxes[primaryJmapId] = ownMailboxes;
-      }
+      publish(a.id, ownMailboxes);
+      // Also cache under the JMAP id so `accountMailboxes[email.sourceAccountId]`
+      // resolves uniformly for personal and shared sources alike.
+      publish(primaryJmapId, ownMailboxes);
 
       if (includeGroup) {
         const sharedByOwner = new Map<string, Mailbox[]>();
@@ -1149,7 +1153,7 @@ export async function buildUnifiedAccountClients(
           // Cache the owner's mailbox list keyed by its JMAP id so single-email
           // and batch actions can resolve role-based destinations (trash/archive)
           // in the owner account instead of falling back to the active account.
-          if (fresh) fetchedMailboxes[ownerId] = ownerMailboxes;
+          publish(ownerId, ownerMailboxes);
         }
       }
     } catch {