Merge pull request #13285 from MicrosoftDocs/Identity-chrisda

Added Caution alert to Identity param 3

Author: chrisda

exchange/exchange-ps/ExchangePowerShell/Get-MailContact.md

@@ -87,6 +87,8 @@ The Identity parameter specifies the mail contact that you want to view. You can
 - Email address
 - GUID
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailContactIdParameter
 Parameter Sets: Identity

exchange/exchange-ps/ExchangePowerShell/Get-MailPublicFolder.md

@@ -85,6 +85,8 @@ The Identity parameter specifies the GUID or public folder name that represents
 
 You can omit the parameter label so that only the public folder name or GUID is supplied.
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailPublicFolderIdParameter
 Parameter Sets: Identity

exchange/exchange-ps/ExchangePowerShell/Get-MailUser.md

@@ -99,6 +99,8 @@ The Identity parameter specifies the mail user that you want to view. You can us
 - Email address
 - GUID
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailUserIdParameter
 Parameter Sets: Identity

exchange/exchange-ps/ExchangePowerShell/Get-MailboxIRMAccess.md

@@ -73,6 +73,8 @@ The Identity parameter specifies the mailbox where you want to view delegate acc
 - SamAccountName
 - User ID or user principal name (UPN)
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailboxIdParameter
 Parameter Sets: (All)

exchange/exchange-ps/ExchangePowerShell/Get-MailboxJunkEmailConfiguration.md

@@ -86,6 +86,8 @@ The Identity parameter specifies the mailbox that you want to view. You can use
 
 You can use the wildcard character (\*) to identify multiple mailboxes.
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailboxIdParameter
 Parameter Sets: (All)

exchange/exchange-ps/ExchangePowerShell/Get-MailboxLocation.md

@@ -114,6 +114,8 @@ In Exchange Online, you can find the TenantGUID and MailboxGUID values after you
 
 You can't use this parameter with the User parameter.
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailboxLocationIdParameter
 Parameter Sets: Identity

exchange/exchange-ps/ExchangePowerShell/Get-MailboxMessageConfiguration.md

@@ -75,6 +75,8 @@ The Identity parameter specifies the mailbox. You can use any value that uniquel
 - SamAccountName
 - User ID or user principal name (UPN)
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailboxIdParameter
 Parameter Sets: (All)

exchange/exchange-ps/ExchangePowerShell/Get-MailboxPermission.md

@@ -114,6 +114,8 @@ The Identity parameter specifies the mailbox you want to view. You can use any v
 - SamAccountName
 - User ID or user principal name (UPN)
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailboxIdParameter
 Parameter Sets: (All)

exchange/exchange-ps/ExchangePowerShell/Get-MailboxPlan.md

@@ -67,6 +67,8 @@ The Identity parameter specifies the mailbox plan that you want to view. You can
 - Distinguished name (DN)
 - GUID
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailboxPlanIdParameter
 Parameter Sets: (All)

exchange/exchange-ps/ExchangePowerShell/Get-MailboxRegionalConfiguration.md

@@ -89,6 +89,8 @@ The Identity parameter specifies the mailbox that you want to view. You can use
 - SamAccountName
 - User ID or user principal name (UPN)
 
+**Caution**: The value $null or a non-existent value for the Identity parameter returns *all* objects as if you ran the Get- command without the Identity parameter. Verify any lists of values for the Identity parameter are accurate and don't contain non-existent $null values.
+
 ```yaml
 Type: MailboxIdParameter
 Parameter Sets: Default, Identity