Using Dynamic Email Disclaimer with Embedded Images and Variables in Exchange Server and IIS SMTP Service

Why Email Disclaimer/Signature is Important

In recent years, many regulations about email for commercial communication have come into force in varies countries.

Germany has laws requiring companies to disclose their company name, registration number, place of registration etc. in e-mail signatures. Ireland’s Director of Corporate Enforcement requires all limited companies operating websites to disclose such information in their emails.

The UK’s ECommerce Regulations require this information in all emails from limited companies as well. While criticized by some as overly bureaucratic, these regulations only extend existing laws for (paper) business correspondence to email. Any infringement to these regulations will result in lawsuits.

Even if your country has no similar regulation, it is still worth to append an email disclaimer in every email as in some situations it may protect you from liability in a court of law.

How Disclaimer Plugin Works?

In Exchange Server 2007/2010/2013/2016, Disclaimer Plugin works as a transport agent, and it works as a SMTP event sink in IIS SMTP Service. It can append/insert disclaimer or signature to email body based on specific rules.

A disclaimer/signature rule can be set for specified sender, domain, group, recipient or email subject.

Create Disclaimer/Signature Rule

You can create a test disclaimer/signature rule for a user like this:

• Click Disclaimer/Signature -> New,
• Input any description for current rule,
• Input user email address in Sender Address,
• Click Edit disclaimer/signature to open disclaimer editor, input some text, click OK,
• Finally, click Save to save current rule.

After rule is saved, click Test, current rule will be executed with a virtual email message, you can find the result in test dialog box.

If Test all rules is checked, all rules defined on current machine will be executed with a virtual email message.

If test result looks good, you can send a test email from that user, and check if received email body has disclaimer/signature appended.

Sender Address Pattern and Wildcard

A single email address or email address with wildcard (* and ?) can be used in Sender Address. It indicates current rule is only enabled for matched sender address.

Here are some examples:

If Sender address matches the following pattern, add disclaimer/signature
				test@emailarchitect.net
			
# This rule is enabled for all emails from test@emailarchitect.net

If Sender address matches the following pattern, add disclaimer/signature
				*@emailarchitect.net
			
			# This rule is enabled for all emails from *@emailarchitect.net
			

If Sender address does not match the following patter, add disclaimer/signature
				test@emailarchitect.net
			
# This rule is enabled for all emails except test@emailarchitect.net

If Sender address does not match the following pattern, add disclaimer/signature
				*@emailarchitect.net
			
# This rule is enabled for all emails except *@emailarchitect.net.

Sender Group, Recipient and Subject Conditions

Besides sender address pattern, you can set additional conditions for sender group, recipient and email subject.

For example, click Add more conditions and change sender condition like this:

If Sender is in one of group:
	IT
	Sales

That means current rule is just enabled for sender that is in “IT” or “Sales” user group.

Disclaimer/Signature Editor

You can use disclaimer/signature editor to change font style, size, color and etc. Moreover, it provides two advanced functions:

• Insert ADSI variables,
• Insert disclaimer/signature from templates.

Use ADSI Variables in Dynamic Email Disclaimer/Signature

ADSI Variables is used to personalize dynamic disclaimer or signature by utilizing user’s Active Directory objects attribute. To add an attribute, use this syntax: {$adsi:AttributeName}, where “AttributeName” is the attribute you want to include in the disclaimer.

Build Dynamic Signature with Variables

To learn how to use variables, let’s create a rule is like this:

If Sender address matches the following pattern, add disclaimer/signature
				*@emailarchitect.net
			

The above rule is enabled for all emails from *@emailarchitect.net, then include some ADSI variables in the disclaimer/signature like this:

The following illustrates what email recipient see - all ADSI variables were replaced by the actual value in Active Directory User Attributes.

From the above example, you can see one rule can generate dynamic disclaimer/signature for individual user at domain level.

How to Set Active Directory User Attributes

Go to Administrative Tools -> Active Directory Users and Computers -> Users, then select the user account you want to edit, right click -> Properties and edit it. In Exchange 2010 or later version, user can edit his contact information via Exchange Server Web Access -> Options -> Account Information.

How to Get Attribute Name

ADSI variable syntax is: {$adsi:AttributeName}. Please note “AttributeName” is not the same as what you see in Active Directory User properties. You need to use “ADSIEdit” tool to find out the real “AttributeName”.

Open “ ADSIEdit” by Administrative Tools -> ADSI Edit, then right click -> Connect To and Click OK by default setting, go to CN-Users node, and select one of Exchange User -> right click -> Properties. You will see the real “AttributeName” in the first column of the following dialog:

Common ADSI Variables

In disclaimer editor -> “ Insert ADSI variable”, it lists most common active directory user attributes. You can click the attribute name to insert it into editor current position.

Insert Embedded Company Logo/Image in Email Disclaimer/Signature Editor

Although a remote logo/image can be used in disclaimer/signature, by default, the image won’t be displayed due to email client security policy.

To fix it, you can add logo/image by clicking Insert image, those images will be attached as embedded attachment in an email.

Embedded image is always displayed in email client by default.

Download Remote Image/Logo as Embedded Attachment

If there are some remote images in disclaimer/signature content, the editor will prompt “Do you want to download remote image as embedded attachment?” after OK is clicked. You can click Yes to download all remote images as embedded attachments.

Use Disclaimer/Signature Templates

In disclaimer/signature editor, four Signature Layout Templates and one Confidentiality Notice are provided.

You can click Insert content from templates from the toolbar, select a template, edit necessary variables, images, click Insert, template content will be inserted into editor.

Insert or Append Disclaimer/Signature intelligently

This is a default option to specify disclaimer/signature position in email body.

It appends disclaimer/signature to the end of email body in new email. On the other hand, it inserts disclaimer/signature before original body content in replied/forwarded email.

Using this option can place disclaimer/signature at better position in email body.

Multiple Disclaimer Rules

You can define multiple rules for individual user or a group. If If current rule is applied, skip next rule is not checked in Advanced options, all rules will be applied to the matched email based on rule priority.

For example:

# rule 1
If Sender address matches the following pattern, add disclaimer/signature
                *@exch27.server
# add personal signature for users in domain level.
#rule 2
If Sender address matches the following pattern, add disclaimer/signature
                *
# add a global Confidentiality Notice

Then the disclaimer/signature for a domain user is like this: