Both the Custom Attributes and the Additional Azure Attributes features are both useful for adding additional, non-standard user information to your signatures. Each differs in the amount of data that is available, and in usage requirements.
Custom attributes use the 15 available Custom Attribute fields that already exist within Office 365 mailboxes (under the General > More Options section - see below):
Only attributes containing data are synchronised from Office 365 to Azure AD (where Exclaimer can reach them).
- This option can be used by anyone using Office 365
- It uses the Custom Attributes fields, available within Exchange Online
- A maximum of 15 custom attributes can be used
Additional Azure AD Attributes
The Sync all AD attributes option is only available if you synchronise from a local Active Directory, using the Azure AD Connect tool.
- This option can be used if you synchronise from a local Active Directory, and using the Azure AD Connect tool.
- Attributes can be selected from the standard range of attributes in the Active Directory
- Any single value attribute fields containing data are synchronised, and available for use within Exclaimer
- Multi-value fields (such as Description) cannot be synchronised
- A maximum of 100 attributes can be synchronised
- Only attributes containing data are synchronised from Office 365 to Azure AD, where Exclaimer can reach them.
- What are Additional Azure AD Attributes?
- Can I Use Both Custom Attributes and Additional Azure AD Attributes?
- What If I'm Using Custom Attributes and Want to Switch to Additional Azure AD Attributes?
- Configuring Azure AD Connect to Synchronize Attributes to Azure
- Using Graph Explorer to Troubleshoot Missing Data
- Which Fields are Multi-Value and Cannot be Synced to Exclaimer?