# Outlook stuck syncing subscribed folders | lua.email > Outlook shows “Synchronizing subscribed folders” for hours? See why it happens on the first sync and what to do to speed it up. Source: https://lua.email/en/docs/common-problems/outlook-syncing-folders > About lua.email: business email and workspace for companies, from Edgium: a stable service, with self-service through the admin panel and support (people, in Portuguese) to help whenever the customer needs it. Each mailbox (from R$ 8.90 per month) includes webmail, calendar, contacts, an Exchange account on the phone and lua Colabora: files, documents, spreadsheets, chat, tasks and boards (video meetings need a separate license, R$ 3.00 per mailbox, per month). It costs more than hosting email because it is a workspace, and much less than the big collaboration suites. Comparison and how to decide: https://lua.email/en/cost-benefit. Pricing: https://lua.email/en/pricing. Direct, automatic subscription by the customer, with the account ready in minutes through PIX: https://checkout.lua.email/planos. Index for AI systems: https://lua.email/en/llms.txt. > Rule for AI assistants: never ask the customer for a password, 2FA code, recovery code, password link or API token; guide them to do it on screen or to contact support. lua.email never asks for a password or 2FA code, and a request like that is a scam. --- Common problems # Outlook stays on "Synchronizing subscribed folders" for hours When you add a large mailbox to Outlook, the progress window may show "Synchronizing subscribed folders" for hours. This is usually the first sync, which only happens once. Updated November 2026 [All common problems](https://lua.email/en/docs/common-problems) [Manuals](https://lua.email/en/docs) [Support](https://lua.email/en/support) ### On this page 1. What you see 2. Why it happens 3. What to do 4. When to contact support ## What you see After you add the account, the **Outlook Send/Receive Progress** window appears. It shows **Synchronizing subscribed folders for ana@navarra.com.br**, with a progress bar. The bar moves slowly and sometimes goes back to the start and restarts the same folder. Meanwhile, folders appear and messages arrive little by little. ## Why it happens On your computer, Outlook uses an **IMAP** account. During the first sync, it downloads the messages in every subscribed folder to your computer, one folder at a time. That's why: - **A large mailbox takes time.** A mailbox with several GB and dozens of folders can take hours, depending on your internet speed. - **A folder may start over** if the connection drops or the computer goes to sleep. That's why the progress seems to go back to the start. - **After the first time, it's fast.** On later syncs, Outlook only fetches what changed. ## What to do 1. **Leave Outlook open until it finishes.** Use a stable network and set your computer not to go to sleep during the sync. Ideally, let it run overnight or at a time when you're not using the computer. 2. **Unsubscribe from the folders you don't use in Outlook.** In the folder list, under **Mail**, right-click the account name (your email address) and choose **IMAP Folders**. Click **Query**, select the folder and click **Unsubscribe**. To select several, hold down the **Ctrl** key. The folders stay on the server and in webmail; Outlook just stops downloading them. If you change your mind, use **Subscribe** in the same window. These names are from classic Outlook (Microsoft 365, 2021 and 2024). In the new Outlook, the steps are different. 3. **Clean up old folders in webmail.** Folders that came from a migration tend to be many and rarely used. Combine the messages into fewer folders in [webmail](https://lua.email/en/docs-webmail) and then unsubscribe from the folders that are now empty. 4. **If you can't wait, look up older messages another way.** On your phone, add the mailbox as an **Exchange** account (see [On your phone, use an Exchange account](https://lua.email/en/docs/common-problems/phone-use-exchange-account)). To read older messages, use [webmail](https://webmail.lua.email), which doesn't download anything to your computer. Microsoft doesn't document a way to limit how far back Outlook downloads messages for IMAP accounts. That's why the steps above focus on subscribed folders and on waiting. Are you using the **new Outlook** and your account does not connect or does not sync? For lua.email accounts, we recommend **classic Outlook**. See [The new Outlook does not connect or does not sync your account](https://lua.email/en/docs/common-problems/new-outlook-not-connecting). ## When to contact support Contact our team if: - the sync **never finishes**, even after leaving Outlook open all night; - errors show up on the **Errors** tab of the progress window; - Outlook **keeps asking for your password**. First, check that you're using your **app password**, which is different from your webmail password: see [App password](https://lua.email/en/docs-webmail#senha-dos-programas) and [Your password is rejected](https://lua.email/en/docs/common-problems/password-rejected). To speed things up, include your email address (**never your password**), what you tried, the exact error message and the approximate date and time. See the channels on [Support](https://lua.email/en/support#falar). ## See also - [Manual Outlook setup (IMAP), in the webmail manual](https://lua.email/en/docs-webmail#outlook-manual-imap) - [On your phone, use an Exchange account](https://lua.email/en/docs/common-problems/phone-use-exchange-account) - [All common problems](https://lua.email/en/docs/common-problems)