Commands › Exchange Online

New-SafeAttachmentRule

Exchange Online ExchangeOnlineManagement New-*

Create safe attachment rules in your cloud-based organization.

Quick start script

# New-SafeAttachmentRule — quick start (serv365.ai)
# 1. Connect (app-only shown; interactive: omit the certificate parameters)
Connect-ExchangeOnline -CertificateThumbprint $thumb -AppId $appId -Organization $org

# 2. Capture the current state first — you cannot roll back what you never recorded
$before = Get-SafeAttachmentRule
$before | Format-List

# 3. Make the change (dry run first)
New-SafeAttachmentRule -Name <String> -SafeAttachmentPolicy <SafeAttachmentPolicyIdParameter> -WhatIf
New-SafeAttachmentRule -Name <String> -SafeAttachmentPolicy <SafeAttachmentPolicyIdParameter>

# 4. Verify and diff
$after = Get-SafeAttachmentRule
Compare-Object ($before | Out-String) ($after | Out-String)

Syntax

New-SafeAttachmentRule [-Name] <String> -SafeAttachmentPolicy <SafeAttachmentPolicyIdParameter>
 [-Comments <String>]
 [-Confirm]
 [-Enabled <Boolean>]
 [-ExceptIfRecipientDomainIs <Word[]>]
 [-ExceptIfSentTo <RecipientIdParameter[]>]
 [-ExceptIfSentToMemberOf <RecipientIdParameter[]>]
 [-Priority <Int32>]
 [-RecipientDomainIs <Word[]>]
 [-SentTo <RecipientIdParameter[]>]
 [-SentToMemberOf <RecipientIdParameter[]>]
 [-WhatIf]
 [<CommonParameters>]

Parameters (13)

ParameterTypeRequiredWhat it controls
-Name String yes The Name parameter specifies a unique name for the safe attachment rule. If the value contains spaces, enclose the value in quotation marks (").
-SafeAttachmentPolicy SafeAttachmentPolicyIdParameter yes The SafeAttachmentPolicy parameter specifies the safe attachment policy that's associated with this safe attachment rule. The rule defines the conditions, and the policy defines the actions.
-Comments String The Comments parameter specifies informative comments for the rule, such as what the rule is used for or how it has changed over time. The length of the comment can't exceed 1024 characters.
-Confirm SwitchParameter The Confirm switch specifies whether to show or hide the confirmation prompt. How this switch affects the cmdlet depends on whether the cmdlet requires confirmation before proceeding.
-Enabled Boolean The Enabled parameter specifies whether the rule is enabled. Valid values are:
-ExceptIfRecipientDomainIs Word[] The ExceptIfRecipientDomainIs parameter specifies an exception that looks for recipients with email addresses in the specified domains. You can specify multiple domains separated by commas.
-ExceptIfSentTo RecipientIdParameter[] The ExceptIfSentTo parameter specifies an exception that looks for recipients in messages. You can use any value that uniquely identifies the recipient. For example:
-ExceptIfSentToMemberOf RecipientIdParameter[] The ExceptIfSentToMemberOf parameter specifies an exception that looks for messages sent to members of distribution groups, mail-enabled security groups, or sent to Microsoft 365 Groups. You can use any value that...
-Priority Int32 The Priority parameter specifies a priority value for the rule that determines the order of rule processing. A lower integer value indicates a higher priority, the value 0 is the highest priority, and rules can't...
-RecipientDomainIs Word[] The RecipientDomainIs parameter specifies a condition that looks for recipients with email addresses in the specified domains. You can specify multiple domains separated by commas.
-SentTo RecipientIdParameter[] The SentTo parameter specifies a condition that looks for recipients in messages. You can use any value that uniquely identifies the recipient. For example:
-SentToMemberOf RecipientIdParameter[] The SentToMemberOf parameter specifies a condition that looks for messages sent to members of distribution groups, mail-enabled security groups, or sent to Microsoft 365 Groups. You can use any value that uniquely...
-WhatIf SwitchParameter The WhatIf switch shows what the command does without making any changes. You don't need to specify a value with this switch.

Reference facts derived from Microsoft documentation, © Microsoft, licensed CC BY 4.0; restructured with original guidance by serv365.ai.