How Dynamics 365 Marketing uses cookies

Dynamics 365 Marketing identifies website visitors using a technology called cookies. A cookie is a small file that's sent by a server and saved by your browser. Each time you visit a server for which a cookie is set, your browser submits that cookie value back to the server. In this way, the cookie can provide a unique visitor ID, which enables the server to return information that is unique to you. This is the technology that originally made the online shopping cart possible.


Many countries/regions (including the European Union) require that you obtain consent before setting a cookie on a resident's machine. It is your organization's responsibility to be aware of, and conform to, all relevant laws and regulations in the markets where you operate, including when it comes to obtaining consent to set cookies. You can read more about the EU regulations at

This page explains how Marketing can help your organization conform to these regulations.

Marketing can generate a small piece of JavaScript code that reads and sets cookies on any page where you place the code. All you need to do to let Marketing record visits to a given page is include the script on that page.

A cookie identifies a single device/browser/account combination. If you use two different browsers (such as Mozilla Firefox and Internet Explorer on the same computer), each will have its own cookie. Likewise, you'll have different cookies on each device that you use. Another user with their own account on your computer will have yet other cookies. If a device gets deleted and reinstalled, all cookies will also be deleted. Nevertheless, Marketing attempts to resolve the actual marketing contact associated with each unique cookie ID.

Whenever a contact submits a marketing page, Marketing correlates the behavior-analysis cookie ID with the incoming contact data submitted with the marketing page form. In this way, the cookie ID is mapped to a Marketing contact ID, allowing the administrator to determine who has been browsing the site. The system applies its configured duplicated-detection method to determine whether incoming landing-page data should be mapped to an existing contact or to a new contact.

Marketing sets three different types of cookies:

  • Long-term behavioral-analysis cookie: This cookie is set and/or read on any webpage where you have placed a Marketing website behavioral-analysis script. The cookie enables Marketing to score leads based on their level of interaction with a given website. The cookie contains no personal information, but does uniquely identify a specific browser on a specific machine, and Marketing can use it to correlate this ID with an actual contact in the Marketing database. The cookie remains active for two years.
  • Short-term, single-visit cookie: This cookie is also set and/or read on any webpage where you have placed a Marketing website behavioral-analysis script. By default, it expires after just 30 minutes. Marketing uses it to group all page loads by a given visitor that are recorded by the same behavioral-analysis script and that occur within the configured time frame. The cookie will consider all of these as part of a single "visit" to the website.
  • Event website: The event website uses a session cookie to enable contacts to sign in and register for events. Additionally, the event website uses cookies to store the user's language.


The Marketing application also sets cookies to enable sign-in sessions and other technical features. These only affect direct users of Dynamics 365 Marketing (such as your internal marketing personnel), not the general public. Microsoft's standard privacy policy applies for these users.

List of Dynamics 365 Marketing cookies

The table below lists the cookies used by Dynamics 365 Marketing as well as the purpose and properties.

Cookie name Is Essential Purpose First or third party Properties Function (Purpose detail) Source URL/JS
79f08280-5c63-4331-b04d-fb6f39afda51 No Behavior tracking Third party Persistent, secure, HttpOnly Identifies end user(by browser). We set this cookie when end user visits a marketing page or a clicks a link (with tracking enabled). At some point of time, when a form is submitted by this end user, a new contact/lead is created and we leverage the cookie available in the browser to associate previous visits with the newly generated contact/lead. This cookie is set by the service. URL differs for each customer org. It can be seen in the tracking/form loader code: <div class="d365-mkt-config" style="display:none" data-website-id="{websiteid}" data-hostname={GUID}></div>
319af4c0-e197-4de9-8a9b-fe98c8a2ca04 No Session tracking Third party Session, secure, HttpOnly To find out how much time user spent on the page This cookie is set by the service. URL differs for each customer org. It can be seen in the tracking/form loader code: <div class="d365-mkt-config" style="display:none" data-website-id="{websiteid}" data-hostname="{GUID }"></div>
msd365mkttr No Behavior tracking First party Persistent, client-side This is being used for the same purpose as the first cookie(79f08280-5c63-4331-b04d-fb6f39afda51). Only difference is that this cookie is set on the customer domain. In some cases, we are unable to access 3rd party cookies (ex: safari OOB blocks) therefore we set this 1st party cookie to keep functionality. Set by the form loader or website tracking script
msd365mkttrs No Session tracking First party Session, client-side This cookie is similar to (319af4c0-e197-4de9-8a9b-fe98c8a2ca04). Only difference is that it is a first party cookie Set by the form loader or website tracking script

How to disable non-essential Dynamics 365 Marketing cookies

Marketing provides a JavaScript API to help your organization conform with data regulations by disabling non-essential Marketing cookies. By defining the following function in your web pages, Marketing will not set non-essential cookies.

    function d365mktConfigureTracking() {
         return {Anonymize: true};


Without the above code, Marketing will set non-essential cookies by default.

If you use a third-party system to handle consent such as a consent service or a cookie banner, you can instruct Marketing to set non-essential cookies with the following call:

MsCrmMkt.reconfigureTracking({Anonymize: false})

Without non-essential cookies, Marketing's tracking capabilities are limited. In some scenarios, users will appear to be anonymous. For example, form submissions will continue to work correctly as user identification is based on the submitted data not on cookies, but form pre-fill data will not work.

See also

Create and deploy marketing pages
Register link clicks and website visits