Redo of markjjo PR MicrosoftDocs#6139

Author: chrisda

exchange/exchange-ps/exchange/New-CaseHoldPolicy.md

@@ -146,15 +146,13 @@ The ExchangeLocation parameter specifies the mailboxes to include in the policy.
 
 - A distribution group or mail-enabled security group (all mailboxes that are currently members of the group).
 
-To specify a mailbox or distribution group, you can use any value that uniquely identifies it. For example:
+To specify a mailbox or distribution group, you can use the following values:
 
 - Name
 
-- Distinguished name (DN)
+- SMTP address
 
-- Email address
-
-- GUID
+- Azure AD ObjectId (You can use the [Get-AzureADUser](https://docs.microsoft.com/powershell/module/azuread/get-azureaduser?view=azureadps-2.0) cmdlet to obtain this value.)
 
 To enter multiple values, use the following syntax: \<value1\>,\<value2\>,...\<valueX\>. If the values contain spaces or otherwise require quotation marks, use the following syntax: "\<value1\>","\<value2\>",..."\<valueX\>".
 

exchange/exchange-ps/exchange/New-RetentionComplianceRule.md

@@ -234,6 +234,8 @@ The ExcludedItemClasses parameter specifies the types of messages to exclude fro
 
 - IPM.Note.Microsoft.Voicemail.UM.CA
 
+Additionally, you can specify [message classes for Exchange items](https://docs.microsoft.com/office/vba/outlook/concepts/forms/item-types-and-message-classes) and custom or third-party message classes. Note that the values you specify aren't validated, so the parameter accepts any text value.
+
 You can specify multiple item class values by using the syntax "Value1","Value2",..."ValueN".
 
 ```yaml

exchange/exchange-ps/exchange/Set-CaseHoldPolicy.md

@@ -112,15 +112,13 @@ The AddExchangeLocation parameter specifies the mailboxes to add to the list of
 
 - A distribution group or mail-enabled security group (all mailboxes that are currently members of the group).
 
-To specify a mailbox or distribution group, you can use any value that uniquely identifies it. For example:
+To specify a mailbox or distribution group, you can use the following values:
 
 - Name
 
-- Distinguished name (DN)
+- SMTP address
 
-- Email address
-
-- GUID
+- Azure AD ObjectId (You can use the [Get-AzureADUser](https://docs.microsoft.com/powershell/module/azuread/get-azureaduser?view=azureadps-2.0) cmdlet to obtain this value.)
 
 To enter multiple values, use the following syntax: \<value1\>,\<value2\>,...\<valueX\>. If the values contain spaces or otherwise require quotation marks, use the following syntax: "\<value1\>","\<value2\>",..."\<valueX\>".
 

exchange/exchange-ps/exchange/Set-RetentionComplianceRule.md

@@ -223,6 +223,8 @@ The ExcludedItemClasses parameter specifies the types of messages to exclude fro
 
 - IPM.Note.Microsoft.Voicemail.UM.CA
 
+Additionally, you can specify [message classes for Exchange items](https://docs.microsoft.com/office/vba/outlook/concepts/forms/item-types-and-message-classes) and custom or third-party message classes. Note that the values you specify aren't validated, so the parameter accepts any text value.
+
 You can specify multiple item class values by using the syntax "Value1","Value2",..."ValueN".
 
 ```yaml