Meeting Invite Updates (Windows client) - Formatting Dial-In String & Link to Join
Published Dec 08 2016 02:15 PM 35.8K Views


Since I originally authored this article, the behavior for the meeting invites has changed, with respect to the Join by phone section.


2016 MSI:


2015 MSI:


Click-to-Run (C2R): the behavior noted in the KBs above is available starting with version 16.0.8431.2046. However, the new format is enabled by default (in the MSI builds it is disabled and needs to be enabled with a registry value). To disable the behavior, create the OneTapJoinForPSTNCallingOnMobile registry entry (as noted in the above support articles) and set this to 0. NOTE: Disabling this will reset it back to a hyperlink, however it will not include the access code as part of the hyperlink.


When enabled, the new meeting invite looks as follows:




On the desktop, it is no longer a hyperlink; however, on mobile, it will render as a hyperlink. The user experience, from the mobile side, is outlined here:


-------- (this section is outdated)--------

Based on feedback we’ve heard from our customers, we’ve made a few updates to Meeting Invites that are generated by the Skype for Business desktop client. In this blog post, we’ll focus on two new additions – the formatting of the dial-in string, and a link to join using the web app. Let’s take a look!


Join by Phone updates


In the meeting invite, the “Join by phone” section now creates hyperlinks for the dial-in numbers that includes a pause (the comma) followed by the Conference ID. This is especially useful when a user wants to join the conference using a mobile phone that doesn’t have the Skype for Business mobile app installed. When the hyperlink is clicked, it allows the dial-out to first dial the bridge number (1-866-679-9995), then pause, then send the Conference ID (75818576) through DTMF tones, completing with the pound (#) sign. The purpose here is to allow one-click join into the dial-in portion of the conference, without having to manually enter the conference ID.


The requirements for the formatting of the dial-in number as tel:<phone number>,<conference id># are as follows:

  1. For an online user (hosted in Office365), the meeting organizer needs a license for Cloud PSTN Conferencing (CPC). They also need to be leveraging Dynamic PSTN meetings.
  2. For an on-premises user, no requirements are needed server-side.
  3. Limitations on Outlook Client versions are as follows:
    • Outlook 2016 Click to Run (C2R) installs only. Minimum version 16.0.7369.2038 (Current Channel - October 2016).
    • Outlook 2016 MSI installs will not work.
    • Outlook 2013 C2R and MSI installs will not work.
    • The meeting needs to be created using Outlook Client. (Outlook Web App [OWA] won’t work)

-------- (end outdated section)--------


Meeting Join URLs
In addition to the formatting for Join by phone, we’ve added a hyperlink that allows joining directly using the Skype Web App. In this instance, the user would be able to participate in the meeting using the web application, even if they have the Skype for Business client installed locally. This is useful if the user is having difficulty joining the meeting using the full client. Many folks already know about this workaround, but for those that don’t, here’s a little background.




When you create a meeting, there is a meeting join URL that is constructed for the meeting, which looks like this:, (this is hyperlinked as Join Skype Meeting in the invite) along with relevant dial-in information (such as the dial-in numbers, toll-free and toll if available) as well as the Conference ID.

If you focus on the meeting join URL, you can break it down as follows:

  • -> this is the location of the meeting, also known as the Meet Simple URL. In this example, this is a meeting hosted in Office365.
  • /microsoft/bryanyce/ -> this is the company and organizer information. In this example, this is in the Microsoft tenant, and the organizer is me (bryanyce)
  • /RY1MVVR1 -> this is the Focus ID of the meeting

It’s important to understand that in the Online world, the meeting join URL is always a unique URL; meaning, the Focus ID of the meeting is always different. In the on-premises world, if you went into Meeting Options for the meeting, you would see this:



“My dedicated meeting space” means that the Focus ID would always be the same, for every meeting that you scheduled, so your join URLs would all be identical.

“A new meeting space” means that the Focus ID would be unique for every meeting.

However, when your account is hosted in Office365, you see this:




Notice that you don’t see the two radio buttons as before? That’s because in online, the behavior is always equivalent to “A new meeting space”. By the way, this also has nothing to do with the new Dynamic IDs feature that we enabled. That feature is specifically for the dial-in coordinates of the meeting (the conference ID), and not the meeting URL (which is why, after your tenant has been enabled for Dynamic IDs, you don’t see any change in the Meeting Options – some folks expected to get the radio buttons as we had on-premises, but that is not the case).

Join Skype Meeting updates
Now, with the history out of the way – what exactly did we do? Well, you can take that same meeting URL ( and by simply appending ?sl=1 to the end, force the join launcher to use the Skype Web App, instead of trying to launch the full client. The URL ends up as (which we show as “Try Skype Web App” in the invite) – allowing the user to go straight to the web client. This is helpful in situations where joining through the full client fails.



Version history
Last update:
‎Oct 12 2017 08:05 AM
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