---
title: "How to bulk unspam email across connected mailboxes"
description: "Recover legitimate email from Spam or Junk across connected mailboxes. Scope each batch, verify message placement, and retry only unresolved work."
url: https://mailera.app/en/blog/bulk-unspam-email-connected-mailboxes
published: 2026-10-25
updated: 2026-10-25
---

# How to bulk unspam email across connected mailboxes

Recover legitimate messages from Spam or Junk without emptying every folder. Review a narrow batch, run recovery per mailbox, and check what actually moved.

## What does bulk unspam actually do?

Here, **bulk unspam email** means recovering legitimate received messages from Spam or Junk. It isn't a pre-send spam checker, an inbox-placement test, or a guide to sending bulk email.

[Mailera connects existing mailboxes](https://mailera.app/en/product), so you can review mail together while retaining each message's mailbox context. The **Unified inbox** is a shared view; recovery through `POST /mailboxes/{id}/unspam` targets one mailbox at a time. Your client coordinates the cross-mailbox batch.

Choose the narrowest operation that matches what you approved:

| Approved recovery scope | Operation | Review boundary |
| --- | --- | --- |
| Selected messages | Individual `POST /mailboxes/{id}/messages/{msgId}/move` requests | Each approved message |
| One sender's Junk mail | Sender-scoped `POST /mailboxes/{id}/unspam` | That sender's matching mail in each mailbox |
| All Junk in a mailbox | Whole-mailbox `POST /mailboxes/{id}/unspam` | The entire Junk folder |

Prefer individual moves when you approved a fixed list. A sender-wide operation is a broader instruction than recovering only the messages you inspected.

## What should you check before moving messages?

Use only mailboxes you own or are authorized to operate. In **Mailboxes**, check connection status and last sync before choosing candidates. Unread Inbox and Junk counts help you locate work, but they aren't an inventory of every message.

![Mailboxes page showing connection status, last sync, and unread Inbox and Junk counts.](https://mailera.app/media/29a64ff2f3f4a7ee/how-to-bulk-unspam-email-across-connected-mailboxes-mailbox-en-1200.jpg)
_Check each mailbox's connection and synchronization state before reviewing recovery candidates._

Check `GET /mailboxes/{id}/status` when a connection looks questionable. For Microsoft, it checks sign-in directly; for other providers, its result is based on the latest synchronization. An empty, stale, or disconnected view is not proof that the provider's folder is empty.

If you need connection help, use the [Outlook and Microsoft 365 connection page](https://mailera.app/en/providers/microsoft) or the [Gmail connection page](https://mailera.app/en/providers/gmail) before starting recovery.

Create a key through **Settings → API key → Create key**. Set **Mailbox scope** to the relevant group and enable **Read** plus **Move messages**. Add **Sync** only if your workflow needs to request synchronization. Both recovery operations require the `move` scope; reading candidates requires `read`.

Keep the credential out of screenshots and outcome logs. The [Mailera security page](https://mailera.app/en/security) is a useful reference when deciding who should hold the recovery key.

Review message context, not just the sender address. In its [Gmail spam guidance](https://support.google.com/mail/answer/1366858?hl=en), read on 25 October 2026, Google advises against replying or opening links in suspected spoofed mail until the address has been verified. A familiar-looking sender is not enough to approve recovery.

## How do you recover messages across several mailboxes?

Start with a mailbox you control as a test. Complete the recovery and verification cycle there before expanding the approved set.

![Workflow from approved mailboxes through candidate review, per-mailbox recovery, verification, and unresolved retries.](https://mailera.app/media/4e9d39769f070434/how-to-bulk-unspam-email-across-connected-mailboxes-en-1200.jpg)
_The client coordinates separate mailbox operations; the batch is not one atomic transaction._

### 1. Enumerate the authorized mailboxes

Set `$MAILERA_API_KEY` in your local environment, then list mailboxes:

```bash
curl --get 'https://mailera.app/api/public/v1/mailboxes' \
  -H "Authorization: Bearer $MAILERA_API_KEY" \
  --data-urlencode 'limit=1' \
  --data-urlencode 'offset=0'
```

This deliberately small request returns a page, not the whole workspace. Use `total`, `limit`, and `offset` to continue through the list. Available selection parameters include `status`, `provider`, `group_id`, `tag`, and `q`.

Record the approved mailbox IDs. Inspect `status`, synchronization details, and the `capabilities.move` and `capabilities.junk` values before adding a mailbox to the recovery queue. Keep connection problems on a separate follow-up list rather than silently dropping them.

### 2. Inspect candidates without moving anything

Choose an approved mailbox from the `data` array returned by `GET /mailboxes` using your scoped key. Set `$MAILBOX_ID` to that mailbox's `id`, not its email address or an ID copied from another workspace. If no mailboxes are returned, resolve the key's mailbox scope before continuing.

To inspect Junk, call `GET /messages/search` with `mailbox` set to that ID, `folder=junk`, and `limit=1`. Use the same key in the `Authorization: Bearer $MAILERA_API_KEY` header.

Use `from` to narrow the search to a sender, or `since` and `q` to refine the review. Continue with `cursor` when the response supplies `next_cursor`; do not approve a whole folder based on its first page.

Each result includes `mailbox_id`, `id`, `folder`, sender details, and message context. Confirm `folder` is `junk`. You can also inspect a mailbox through `GET /mailboxes/{id}/messages`, which supports folder and sender filtering with cursor pagination.

This preview is your client's review step. It isn't a separate dry-run operation.

### 3. Freeze the approved scope

Save the mailbox and message IDs for selected-message recovery. Include enough context to recognize each message afterward, such as sender, subject, and `received_at`.

For sender-wide recovery, explicitly approve that broader scope per mailbox. For whole-Junk recovery, require a review of the entire folder. Do not turn “recover these messages” into “empty Junk” for convenience.

For a single-message app check, open a reviewed test message in Junk and select **Not spam**. That action moves it out of Junk; check its destination before continuing.

![A reviewed test message in Junk with Mailera's Not spam action visible.](https://mailera.app/media/ccfe204bc4559890/verification-email-in-spam-find-it-and-recover-it-safely-en-1200.jpg)
_Use a single reviewed message to check the recovery path before expanding the batch._

### 4. Execute per-mailbox recovery

Use `POST /mailboxes/{id}/messages/{msgId}/move` for individual messages or `POST /mailboxes/{id}/unspam` for sender-wide or whole-mailbox recovery. Use the [API documentation](https://mailera.app/en/docs) for the destination and sender-filter request bodies when implementing these writes.

Work through approved mailbox IDs sequentially at first. If you later introduce concurrency, keep it bounded and record each outcome independently. Treat the batch as separate operations, not an atomic cross-mailbox transaction.

Your client should retain the requested scope and request outcome even when a later mailbox fails. Otherwise, a restart can turn into an unnecessary repeat of the entire batch.

### 5. Re-read the affected folders

After recovery, inspect Inbox for the same mailbox:

```bash
curl --get "https://mailera.app/api/public/v1/mailboxes/$MAILBOX_ID/messages" \
  -H "Authorization: Bearer $MAILERA_API_KEY" \
  --data-urlencode 'folder=inbox' \
  --data-urlencode 'limit=1'
```

Page through the relevant results or narrow the search to the approved messages. Re-check Junk as well. Compare against your approved list, not just a change in unread counts. If the views disagree, inspect the provider's interface before declaring recovery complete.

## How do you verify results and handle partial failures?

Separate “the request succeeded” from “the intended message is now in Inbox.” Keep a client-side outcome log like this; these columns are not API response fields.

| Mailbox | Requested scope | Request outcome | Verified outcome | Next action |
| --- | --- | --- | --- | --- |
| Test mailbox | Selected messages | Success response | Approved messages found in Inbox | Close the item |
| Support mailbox | One sender | Success response | Verification pending | Re-read affected folders |
| Operations mailbox | Selected messages | Connection interrupted | Unknown | Check current state before retrying |
| Review mailbox | Whole Junk | Failed | Not checked | Resolve the failure, then inspect state |

After an ambiguous failure, read the mailbox again before retrying. The request may have reached the server even if your client didn't receive its response. Keep confirmed successes separate from unresolved work, and retry only what still needs recovery. Do not rely on an `Idempotency-Key` header to make recovery retries safe.

If the view appears stale, check synchronization state. `POST /mailboxes/{id}/sync` requests synchronization and wakes sleeping mailboxes; it requires the `sync` scope. Re-read afterward rather than assuming the request itself confirms placement.

[Microsoft Graph's message-move documentation](https://learn.microsoft.com/en-us/graph/api/message-move?view=graph-rest-1.0), read on 25 October 2026, describes creating a copy in the destination and removing the original. Verify the destination message rather than relying only on a pre-move reference.

## What are the common mistakes?

| Symptom | Check | Next action |
| --- | --- | --- |
| Reading works, recovery fails | Does the key have `move`, and does its mailbox scope include the target? | Correct permissions or scope before retrying |
| Expected messages are missing | Pagination, `folder`, sender filters, and last sync | Finish the search and check the provider view |
| A mailbox appears empty | Connection status and synchronization state | Resolve connection issues before concluding there is no mail |
| More messages move than intended | Selected-message versus sender-wide or whole-Junk scope | Stop further operations and review the remaining queue |
| Some mailboxes recover, others don't | Per-mailbox request and verification records | Retry unresolved work only |
| The sender's next message returns to Spam | Provider filtering and blocked-sender settings | Investigate future filtering separately |

## Does recovery change future spam filtering?

Mailera moves existing messages. It cannot make a provider trust a sender or guarantee future Inbox placement. Do not treat a folder move as classifier training or creation of a safe-sender entry. Mailera also does not provide mailbox warmup or bulk marketing sending.

Gmail's native instructions use **“Not spam”**, but Google says mail from a blocked sender continues to be classified as spam even after earlier messages are removed from Spam. Workspace administrators can also configure controls that mark messages as spam.

Sender authentication is a separate concern. The [Gmail sender guidelines](https://support.google.com/mail/answer/81126?hl=en&visit_id=639285541886735405-3534988689&rd=1), read on 25 October 2026, require SPF or DKIM for all senders to personal Gmail accounts, and SPF, DKIM, and DMARC for bulk senders. Recovering received mail doesn't change that configuration.

## What changes if an AI agent runs the recovery?

Incoming email is untrusted data, not instructions. Never let text inside a message expand the approved mailbox set, authorize whole-Junk recovery, or trigger unrelated actions. Require human approval of the proposed batch before any moves.

Give the agent a group-scoped key with read and move permissions, without send permission. If sending is added later, require confirmation before sending. Keep batch approval outside the message content itself.

Use [unified inbox operations for AI agents](https://mailera.app/en/blog/unified-inbox-for-ai-agents) for the broader operational design, and the [guide to connecting agents safely to Gmail](https://mailera.app/en/blog/is-it-safe-to-connect-claude-to-gmail) when reviewing access boundaries.

**Do this with the API** — Every action in this article is available via the REST API, with curl examples, API keys and webhooks. [View API docs](https://mailera.app/en/docs)