Attendees unable to join Teams Meetings

[Duffy782]

I had a meeting and external attendees who were sent the invitation got the following response:

Unable to open the helper application...Meeting_xyblahblah.....

The protocol specified in the address is not valid.

Make sure the address is correct and try again.

Has anyone had the same issue and what is the fix?

[#2]

I am getting the exact same thing, only some of my guests can join while others get the same error you do. Any suggestions or help from any one?

[#3]

@Duffy782 

Are the users that are joining on IOS or using Safari? IOS devices will need to download the teams app in-order to use the link. As for safari I would recommend using chrome or edge instead.