New-SyncMailPublicFolder

The AcceptMessagesOnlyFrom parameter specifies who is allowed to send messages to this recipient. Messages from other senders are rejected.

Valid values for this parameter are individual senders in your organization (mailboxes, mail users, and mail contacts). You can use any value that uniquely identifies the sender. For example:

• Name
• Alias
• Distinguished name (DN)
• Canonical DN
• Email address
• GUID

You can specify multiple senders separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Sender1","Sender2",..."SenderN".

The senders you specify for this parameter are automatically copied to the AcceptMessagesOnlyFromSendersOrMembers property. Therefore, you can't use the AcceptMessagesOnlyFrom and AcceptMessagesOnlyFromSendersOrMembers parameters in the same command.

By default, this parameter is blank ($null), which allows this recipient to accept messages from all senders.

The Alias parameter specifies the Exchange alias (also known as the mail nickname) for the recipient. This value identifies the recipient as a mail-enabled object, and shouldn't be confused with multiple email addresses for the same recipient (also known as proxy addresses). A recipient can have only one Alias value. The maximum length is 64 characters.

The Alias value can contain letters, numbers and the following characters:

• !, #, %, *, +, -, /, =, ?, ^, _, and ~.
• $, &, ', `, {, }, and | need to be escaped (for example -Alias what`'snew) or the entire value enclosed in single quotation marks (for example, -Alias 'what'snew'). The & character is not supported in the Alias value for Microsoft Entra Connect synchronization.
• Periods (.) must be surrounded by other valid characters (for example, help.desk).
• Unicode characters U+00A1 to U+00FF.

When you create a recipient without specifying an email address, the Alias value you specify is used to generate the primary email address (alias@domain). Supported Unicode characters are mapped to best-fit US-ASCII text characters. For example, U+00F6 (ö) is changed to oe in the primary email address.

If you don't use the Alias parameter when you create a recipient, the value of a different required parameter is used for the Alias property value:

• Recipients with user accounts (for example, user mailboxes, and mail users): The left side of the MicrosoftOnlineServicesID or UserPrincipalName parameter is used. For example, [email protected] results in the Alias property value helpdesk.
• Recipients without user accounts (for example, room mailboxes, mail contacts, and distribution groups): The value of the Name parameter is used. Spaces are removed and unsupported characters are converted to question marks (?).

If you modify the Alias value of an existing recipient, the primary email address is automatically updated only in environments where the recipient is subject to email address policies (the EmailAddressPolicyEnabled property is True for the recipient).

The Alias parameter never generates or updates the primary email address of a mail contact or a mail user.

The Confirm switch specifies whether to show or hide the confirmation prompt. How this switch affects the cmdlet depends on if the cmdlet requires confirmation before proceeding.

• Destructive cmdlets (for example, Remove-* cmdlets) have a built-in pause that forces you to acknowledge the command before proceeding. For these cmdlets, you can skip the confirmation prompt by using this exact syntax: -Confirm:$false.
• Most other cmdlets (for example, New-* and Set-* cmdlets) don't have a built-in pause. For these cmdlets, specifying the Confirm switch without a value introduces a pause that forces you acknowledge the command before proceeding.

The Contacts parameter specifies the contacts for the public folder. Contacts are persons about whom you can save several types of information, such as addresses, telephone numbers, and web page URLs.

Valid values for this parameter are recipients in your organization. You can use any value that uniquely identifies the recipient. For example:

• Name
• Alias
• Distinguished name (DN)
• Canonical DN
• Email address
• GUID

You can enter multiple values separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Value1","Value2",..."ValueN".

This parameter specifies a value for the CustomAttribute1 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute10 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute11 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute12 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute13 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute14 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute15 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute2 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute3 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute4 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute5 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute6 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute7 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute8 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

This parameter specifies a value for the CustomAttribute9 property on the recipient. You can use this property to store custom information about the recipient, and to identify the recipient in filters. The maximum length is 1024 characters. If the value contains spaces, enclose the value in quotation marks (").

The DeliverToMailboxAndForward parameter specifies the message delivery behavior when a forwarding address is specified by the ForwardingAddress parameter. Valid values are:

• $true: Messages are delivered to this mail-enabled public folder and forwarded to the specified recipient or email address.
• $false: If a forwarding recipient is configured, messages are delivered only to the specified recipient, and messages aren't delivered to this mail-enabled public folder. If no forwarding recipient is configured, messages are delivered only to this mailbox. This is the default value.

The default value is $false. This parameter is meaningful only if you configure a forwarding recipient by using the ForwardingAddress parameter.

The DisplayName parameter specifies the display name of the mail-enabled public folder. The display name is visible in the Exchange admin center, in address lists, and in Outlook. The maximum length is 256 characters. If the value contains spaces, enclose the value in quotation marks (").

If you don't use the DisplayName parameter, the value of the Name parameter is used for the display name.

This parameter is available only in on-premises Exchange.

The DomainController parameter specifies the domain controller that's used by this cmdlet to read data from or write data to Active Directory. You identify the domain controller by its fully qualified domain name (FQDN). For example, dc01.contoso.com.

The EmailAddresses parameter specifies all email addresses (proxy addresses) for the recipient, including the primary SMTP address. In on-premises Exchange organizations, the primary SMTP address and other proxy addresses are typically set by email address policies. However, you can use this parameter to configure other proxy addresses for the recipient. For more information, see Email address policies in Exchange Server.

Valid syntax for this parameter is "Type:EmailAddress1","Type:EmailAddress2",..."Type:EmailAddressN". The optional Type value specifies the type of email address. Examples of valid values include:

• SMTP: The primary SMTP address. You can use this value only once in a command.
• smtp: Other SMTP email addresses.
• X400: X.400 addresses in on-premises Exchange.
• X500: X.500 addresses in on-premises Exchange.

If you don't include a Type value for an email address, the address is assumed to be an SMTP email address. The syntax of SMTP email addresses is validated, but the syntax of other email address types isn't validated. Therefore, you need to verify that any custom addresses are formatted correctly.

To specify the primary SMTP email address, you can use any of the following methods:

• Use the Type value SMTP on the address.
• The first email address when you don't use any Type values, or when you use multiple lowercase smtp Type values.
• If it's available, use the PrimarySmtpAddress parameter instead. You can't use the EmailAddresses parameter and the PrimarySmtpAddress parameter in the same command.

This parameter is reserved for internal Microsoft use.

The ExternalEmailAddress parameter specifies an email address outside the organization.

The ForwardingAddress parameter specifies a forwarding address for messages that are sent to this mail-enabled public folder. A valid value for this parameter is a recipient in your organization. You can use any value that uniquely identifies the recipient. For example:

• Name
• Alias
• Distinguished name (DN)
• Canonical DN
• Email address
• GUID

How messages are delivered and forwarded is controlled by the DeliverToMailboxAndForward parameter.

• DeliverToMailboxAndForward is $true: Messages are delivered to this mail-enabled public folder and forwarded to the specified recipient.
• DeliverToMailboxAndForward is $false: Messages are only forwarded to the specified recipient. Messages aren't delivered to this mail-enabled public folder.

The default value is blank ($null), which means no forwarding recipient is configured.

The GrantSendOnBehalfTo parameter specifies who can send on behalf of this mail-enabled public folder. Although messages send on behalf of the public folder clearly show the sender in the From field (<Sender> on behalf of <PublicFolder>), replies to these messages are delivered to the public folder, not the sender.

The sender you specify for this parameter must be a mailbox, mail user or mail-enabled security group (a mail-enabled security principal that can have permissions assigned). You can use any value that uniquely identifies the sender. For example:

• Name
• Alias
• Distinguished name (DN)
• Canonical DN
• Email address
• GUID

You can enter multiple values separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Value1","Value2",..."ValueN".

By default, this parameter is blank, which means no one else has permission to send on behalf of this public folder.

The HiddenFromAddressListsEnabled switch specifies that this recipient is not visible in address lists. You don't need to specify a value with this switch.

The MaxReceiveSize parameter specifies the maximum size of a message that can be sent to the mail-enabled public folder. Messages larger than the maximum size are rejected.

When you enter a value, qualify the value with one of the following units:

• B (bytes)
• KB (kilobytes)
• MB (megabytes)
• GB (gigabytes)

Unqualified values are typically treated as bytes, but small values may be rounded up to the nearest kilobyte.

A valid value is a number up to 1.999999 gigabytes (2147483647 bytes) or the value unlimited. The default value is unlimited, which indicates the maximum size is imposed elsewhere (for example, organization, server, or connector limits).

Base64 encoding increases the size of messages by approximately 33%, so specify a value that's 33% larger than the actual maximum message size that you want to enforce. For example, the value 64 MB results in a maximum message size of approximately 48 MB.

The MaxSendSize parameter specifies the maximum size of a message that can be sent by the mail-enabled public folder.

When you enter a value, qualify the value with one of the following units:

• B (bytes)
• KB (kilobytes)
• MB (megabytes)
• GB (gigabytes)

Unqualified values are typically treated as bytes, but small values may be rounded up to the nearest kilobyte.

A valid value is a number up to 1.999999 gigabytes (2147483647 bytes) or the value unlimited. The default value is unlimited, which indicates the maximum size is imposed elsewhere (for example, organization, server, or connector limits).

Base64 encoding increases the size of messages by approximately 33%, so specify a value that's 33% larger than the actual maximum message size that you want to enforce. For example, the value 64 MB results in a maximum message size of approximately 48 MB.

The Name parameter specifies the unique name of the mail-enabled public folder. The maximum length is 64 characters. If the value contains spaces, enclose the value in quotation marks (").

This value is also used for the DisplayName property if you don't use the DisplayName parameter.

The OnPremisesObjectId parameter specifies the GUID of the on-premises mail-enabled public folder that's used to create the mail-enabled public folder object in Exchange Online.

This parameter is reserved for internal Microsoft use.

The RejectMessagesFrom parameter specifies who isn't allowed to send messages to this recipient. Messages from these senders are rejected.

Valid values for this parameter are individual senders in your organization (mailboxes, mail users, and mail contacts). You can use any value that uniquely identifies the sender. For example:

• Name
• Alias
• Distinguished name (DN)
• Canonical DN
• Email address
• GUID

You can specify multiple senders separated by commas. If the values contain spaces or otherwise require quotation marks, use the following syntax: "Sender1","Sender2",..."SenderN".

The senders you specify for this parameter are automatically copied to the RejectMessagesFromSendersOrMembers property. Therefore, you can't use the RejectMessagesFrom and RejectMessagesFromSendersOrMembers parameters in the same command.

By default, this parameter is blank ($null), which allows this recipient to accept messages from all senders.

The RequireSenderAuthenticationEnabled parameter specifies whether to accept messages only from authenticated (internal) senders. Valid values are:

• $true: Messages are accepted only from authenticated (internal) senders. Messages from unauthenticated (external) senders are rejected.
• $false: Messages are accepted from authenticated (internal) and unauthenticated (external) senders.

The WhatIf switch simulates the actions of the command. You can use this switch to view the changes that would occur without actually applying those changes. You don't need to specify a value with this switch.

The WindowsEmailAddress parameter specifies the Windows email address for this recipient. This is a common Active Directory attribute that's present in all environments, including environments without Exchange. Using the WindowsEmailAddress parameter on a recipient has one of the following results:

• In environments where the recipient is subject to email address policies (the EmailAddressPolicyEnabled property is set to the value True for the recipient), the WindowsEmailAddress parameter has no effect on the WindowsEmailAddress property or the primary email address value.
• In environments where the recipient isn't subject to email address policies (the EmailAddressPolicyEnabled property is set to the value False for the recipient), the WindowsEmailAddress parameter updates the WindowsEmailAddress property and the primary email address to the same value.

The WindowsEmailAddress property is visible for the recipient in Active Directory Users and Computers in the E-mail attribute. The attribute common name is E-mail-Addresses, and the Ldap-Display-Name is mail. If you modify this attribute in Active Directory, the recipient's primary email address is not updated to the same value.