---
title: "Test-VEXMailboxResolution"
description: "Tests the availability of Microsoft Exchange mailboxes before a bulk mailbox restore. Product: Veeam Backup & Replication, Veeam Backup for Microsoft 365 Product Edition: Community, Standard, Enterprise, Enterprise Plus, Veeam Universal License This "
canonical: "https://helpcenter.veeam.com/docs/vbo365/explorers_powershell/test-vexmailboxresolution.html"
breadcrumb: "Veeam Explorers PowerShell Reference > Veeam Explorers PowerShell Reference > Veeam Explorer for Microsoft Exchange > Test-VEXMailboxResolution"
dateModified: "2026-08-20"
---

# Test-VEXMailboxResolution

## Short Description
Tests the availability of Microsoft Exchange mailboxes before a bulk mailbox restore.

**Product**: Veeam Backup & Replication, Veeam Backup for Microsoft 365

**Product Edition**: Community, Standard, Enterprise, Enterprise Plus, Veeam Universal License

## Syntax

This cmdlet provides the following parameter sets:

<ul class="syntax-sets">
  <li>
    <p><code>DefaultParameterSet (Default)</code></p>

```
Test-VEXMailboxResolution [-Credential <PSCredential>] -Mailbox <VEXMailbox[]>
 [-Office365Credential <PSCredential>] [-Domain <String>] [-Force] [<CommonParameters>]
```
  </li>
  <li>
    <p><code>OAuthParameterSet</code></p>

```
Test-VEXMailboxResolution [-Credential <PSCredential>] -Mailbox <VEXMailbox[]> -ApplicationId <Guid>
 [-Domain <String>] [-Force] [<CommonParameters>]
```
  </li>
  <li>
    <p><code>OAuthAppOnlyParameterSet</code></p>

```
Test-VEXMailboxResolution [-Credential <PSCredential>] -Mailbox <VEXMailbox[]> -ApplicationId <Guid>
 -ApplicationCertificatePath <String> [-ApplicationCertificatePassword <SecureString>] [-Domain <String>]
 [-Force] [<CommonParameters>]
```
  </li>
</ul>

## Detailed Description
This cmdlet tests the availability of mailboxes. You may want to run this cmdlet before you start a bulk mailbox restore.

## Parameters

<table style="width:100%;" class="Blue_Table">
      <tr style="vertical-align:top">
        <th style="width:20%;">
          <p>Parameter</p>
        </th>
        <th style="width:20%;">
          <p>Description</p>
        </th>
        <th style="width:20%;">
          <p>Type</p>
        </th>
        <th style="width:10%;">
          <p>Required</p>
        </th>
        <th style="width:10%;">
          <p>Position</p>
        </th>
        <th style="width:10%;">
          <p>Accept Pipeline Input</p>
        </th>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">ApplicationCertificatePassword</span></p>
        </td>
        <td>
          <p>To test mailbox resolution using multi-factor authentication.</p><p>Specifies the certificate password. The cmdlet will use this password to confirm the certificate that you want to import to a Microsoft Entra application. After that the cmdlet will set up an encrypted connection to a Microsoft organization and will test the mailbox resolution. This parameter is obligatory.</p>
        </td>
        <td style="width:10%;">
          <p><code>SecureString</code></p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">ApplicationCertificatePath</span></p>
        </td>
        <td>
          <p>To test mailbox resolution using multi-factor authentication.</p><p>Specifies a path to the folder where the certificate is located. The cmdlet will import the certificate that is located in this path to set up an encrypted connection to a Microsoft organization and to test the mailbox resolution.</p>
        </td>
        <td style="width:10%;">
          <p><code>String</code></p>
        </td>
        <td style="width:10%;">
          <p>True</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">ApplicationId</span></p>
        </td>
        <td>
          <p>Specifies a Microsoft Entra application ID. The cmdlet will use this application ID to set up a secure connection to a Microsoft organization.</p><p><strong>Note</strong>: This parameter works for mailboxes that are backed-up with Veeam Backup for Microsoft 365 only.</p>
        </td>
        <td style="width:10%;">
          <p><code>Guid</code></p>
        </td>
        <td style="width:10%;">
          <p>True</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">Credential</span></p>
        </td>
        <td>
          <p>Specifies Windows user credentials to connect to the Active Directory domain and the Exchange server.</p><p>Accepts the <code>PSCredential</code> object. To get this object, run the [`Get-Credential`](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.security/get-credential) cmdlet.</p>
        </td>
        <td style="width:10%;">
          <p><code>PSCredential</code></p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">Domain</span></p>
        </td>
        <td>
          <p>Specifies a mailbox domain.</p>
        </td>
        <td style="width:10%;">
          <p><code>String</code></p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">Force</span></p>
        </td>
        <td>
          <p>Defines that the cmdlet will ignore the certificate upon the connection.</p><p>Default: <em>False</em></p>
        </td>
        <td style="width:10%;">
          <p><code>SwitchParameter</code></p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">Mailbox</span></p>
        </td>
        <td>
          <p>Specifies a mailbox. The cmdlet will check whether this mailbox is available.</p><p>Accepts the <a href="vexmailbox.md"><code>VEXMailbox</code></a><code>[]</code> object. To get this object, run the <a href="get-vexmailbox.md"><code>Get-VEXMailbox</code></a> cmdlet.</p>
        </td>
        <td style="width:10%;">
          <p><a href="vexmailbox.md"><code>VEXMailbox[]</code></a></p>
        </td>
        <td style="width:10%;">
          <p>True</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
      <tr style="vertical-align:top">
        <td>
          <p class="Table_Text_Bold"><span class="Table_Text_Bold">Office365Credential</span></p>
        </td>
        <td>
          <p>Specifies a Microsoft 365 user account credentials to connect to the backup proxy server.</p><p>Accepts the <code>PSCredential</code> object. To get this object, run the [`Get-Credential`](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.security/get-credential) cmdlet.</p>
        </td>
        <td style="width:10%;">
          <p><code>PSCredential</code></p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
        <td style="width:10%;">
          <p>Named</p>
        </td>
        <td style="width:10%;">
          <p>False</p>
        </td>
      </tr>
    </table>

`<CommonParameters>`

This cmdlet supports Microsoft PowerShell common parameters. For more information on common parameters, see the [About Common Parameters](http://go.microsoft.com/fwlink/p/?LinkID=113216) section of Microsoft Learn.

## Examples

::: example
### Example 1. Testing Mailbox Resolution [For Veeam Backup & Replication]

This example shows how to test the availability of Exchange mailboxes.

```
$credentials = Get-Credential
$session = Get-VBRExchangeItemRestoreSession
$database = Get-VEXDatabase -Session $session -Name "DB_0754907780.edb"
$mailbox = Get-VEXMailbox -Database $database
Test-VEXMailboxResolution -Mailbox $mailboxes -Domain test.local -Credential $credentials
```

Perform the following steps:

1. Run the [`Get-Credential`](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.security/get-credential) cmdlet. Type Windows credentials to connect to the Active Directory domain and the Exchange server. Save the result to the `$credentials` variable.
2. Run the [`Get-VBRExchangeItemRestoreSession`](get-vbrexchangeitemrestoresession.md) cmdlet. Save the result to the `$session` variable.
3. Run the [`Get-VEXDatabase`](get-vexdatabase.md) cmdlet. Set the `$session` variable as the `Session` parameter value. Specify the `Name` parameter value. Save the result to the `$database` variable.
4. Run the [`Get-VEXMailbox`](get-vexmailbox.md) cmdlet. Set the `$database` variable as the `Database` parameter value. Save the result to the `$mailbox` variable.
5. Run the `Test-VEXMailboxResolution` cmdlet. Specify the following settings:

   - Set the `$mailbox` variable as the `Mailbox` parameter value.
   - Specify the `Domain` parameter value.
   - Set the `$credentials` variable as the `Credential` parameter value.

:::

::: example
### Example 2. Testing Mailboxes Resolution [For Veeam Backup for Microsoft 365]

This example shows how to test the availability of Exchange mailboxes from the `support3backup.onmicrosoft.com` backed-up Exchange organization.

```
$credentials = Get-Credential
$session = Get-VBOExchangeItemRestoreSession
$database = Get-VEXDatabase -Session $session -Name "support3backup*"
$mailboxes = Get-VEXMailbox -Database $database
Test-VEXMailboxResolution -Mailbox $mailboxes -Domain test.local -Credential $credentials
```

Perform the following steps:

1. Run the [`Get-Credential`](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.security/get-credential) cmdlet to create a credential object. Type Windows credentials to connect to the Active Directory domain and the Exchange server. Save the result to the `$credentials` variable.
2. Run the [`Get-VBOExchangeItemRestoreSession`](get-vboexchangeitemrestoresession.md) cmdlet. Save the result to the `$session` variable.
3. Run the [`Get-VEXDatabase`](get-vexdatabase.md) cmdlet. Set the `$session` variable as the `Session` parameter value. Specify the `Name` parameter value. Use the * wildcard character to substitute the timestamp. Save the result to the `$database` variable.
4. Run the [`Get-VEXMailbox`](get-vexmailbox.md) cmdlet. Set the `$database` variable as the `Database` parameter value. Save the result to the `$mailboxes` variable.
5. Run the `Test-VEXMailboxResolution` cmdlet. Specify the following settings:

   - Set the `$mailboxes` variable as the `Mailbox` parameter value.
   - Specify the `Domain` parameter value.
   - Set the `$credentials` variable as the `Credential` parameter value.

:::

::: example
### Example 3. Testing Mailbox Resolution Using Multi-Factor Authentication with Microsoft Entra Application ID [For Veeam Backup for Microsoft 365]

This example shows how to test the availability of the `Sales` Exchange mailbox. Veeam Backup for Microsoft 365 will use the `76397916-8dcb-4348-96ac-6e2e881f9292` Microsoft Entra application ID to set up a secure connection to a Microsoft organization.

```
$session = Get-VBOExchangeItemRestoreSession
$database = Get-VEXDatabase -Session $session -Name "support3backup*"
$mailbox = Get-VEXMailbox -Database $database -Name "Sales"
Test-VEXMailboxResolution -Mailbox $mailbox -Domain test.local -ApplicationId 76397916-8dcb-4348-96ac-6e2e881f9292
```

Perform the following steps:

1. Run the [`Get-VBOExchangeItemRestoreSession`](get-vboexchangeitemrestoresession.md) cmdlet. Save the result to the `$session` variable.
2. Run the [`Get-VEXDatabase`](get-vexdatabase.md) cmdlet. Set the `$session` variable as the `Session` parameter value. Specify the `Name` parameter value. Use the * wildcard character to substitute the timestamp. Save the result to the `$database` variable.
3. Run the [`Get-VEXMailbox`](get-vexmailbox.md) cmdlet. Set the `$database` variable as the `Database` parameter value. Specify the `Name` parameter value. Save the result to the `$mailbox` variable.
4. Run the `Test-VEXMailboxResolution` cmdlet. Specify the following settings:

   - Set the `$mailbox` variable as the `Mailbox` parameter value.
   - Specify the `Domain` parameter value.
   - Specify the `ApplicationId` parameter value.

5. To set up a secure connection to a Microsoft organization, open the [https://microsoft.com/devicelogin](https://microsoft.com/devicelogin) link in your browser and enter the code that you get in the PowerShell Console to authenticate to the Microsoft 365 server.

:::

::: example
### Example 4. Testing Mailbox Resolution Using Multi-Factor Authentication with Microsoft Entra Application Certificate [For Veeam Backup for Microsoft 365]

This example shows how to test the availability of the `Sales` Exchange mailbox with the Microsoft Entra application certificate.

```
$session = Get-VBOExchangeItemRestoreSession
$database = Get-VEXDatabase -Session $session -Name "support3backup*"
$mailbox = Get-VEXMailbox -Database $database -Name "Sales"
$securepassword = Read-Host "Enter your password" -AsSecureString
Enter your password: **********
Test-VEXMailboxResolution -Mailbox $mailbox -Domain test.local -ApplicationCertificatePath "C:\certificate\cert.pfx" -ApplicationCertificatePassword $securepassword
```

Perform the following steps:

1. Run the [`Get-VBOExchangeItemRestoreSession`](get-vboexchangeitemrestoresession.md) cmdlet. Save the result to the `$session` variable.
2. Run the [`Get-VEXDatabase`](get-vexdatabase.md) cmdlet. Set the `$session` variable as the `Session` parameter value. Specify the `Name` parameter value. Use the * wildcard character to substitute the timestamp. Save the result to the `$database` variable.
3. Run the [`Get-VEXMailbox`](get-vexmailbox.md) cmdlet. Set the `$database` variable as the `Database` parameter value. Specify the `Name` parameter value. Save the result to the `$mailbox` variable.
4. Run the [`Read-Host`](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/read-host) cmdlet. Specify the message that the console will display as a prompt. Provide the `AsSecureString` parameter. Save the result to the `$securepassword` variable.
5. Enter the password.
6. Run the `Test-VEXMailboxResolution` cmdlet. Specify the following settings:

   - Set the `$mailbox` variable as the `Mailbox` parameter value.
   - Specify the `Domain` parameter value.
   - Specify the `ApplicationCertificatePath` parameter value.
   - Set the `$securepassword` variable as the `ApplicationCertificatePassword` parameter value.

7. To set up a secure connection to a Microsoft organization, open the [https://microsoft.com/devicelogin](https://microsoft.com/devicelogin) link in your browser and enter the code that you get in the PowerShell Console to authenticate to the Microsoft 365 server.

:::

## Related Commands

- [`Get-VBOExchangeItemRestoreSession`](get-vboexchangeitemrestoresession.md)
- [`Get-VBRExchangeItemRestoreSession`](get-vbrexchangeitemrestoresession.md)
- [`Get-VEXDatabase`](get-vexdatabase.md)
- [`Get-VEXMailbox`](get-vexmailbox.md)
- [``Get-Credential``](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.security/get-credential)
- [``Read-Host``](https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/read-host)