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Power Automate - Building Flows
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Calendar Event Failure - Optional Invitees Runtime Value to be Converted Doesn't have the expected format 'string/email'.

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Posted on by 63

I have a flow that automatically pulls from a SharePoint List to create a calendar event. I suddenly encountered a new failure that appears to be with the optional attendees. It's strange that it did not create the Calendar event and just fail to invite the attendees though.

 

I have a multi-selection people picker I have parsed to pull the email addresses and create a variable, with the individual emails separated with a semicolon. I then have a place for people to manually enter invitees separated with a semicolon. 

 

Error details:

 

Input parameter 'item/optionalAttendees' is required to be of type 'String/email'. The runtime value '";email1@location.com;;email2@location.comemail3@location.com; email3@location.com"' to be converted doesn't have the expected format 'string/email'.


I can't tell which issue is the issue. Is it because it started with a semicolon? Is it because of the double semicolon? Is it the two emails without any kind of separator jammed together?

 

How can I prevent this from erroring if any of those values are empty? Do I have to encase them in if blanks to make the semicolons dependent on blanks or not blank? I did rearrange my dynamic content to put the email that is always present at the beginning and ensured my semicolons were all present in between each piece of dynamic content and have rerun the flow and it worked but I'd like to make sure this doesn't happen in the future.

 

TIA!

  • CU12092006-0 Profile Picture
    63 on at
    Re: Calendar Event Failure - Optional Invitees Runtime Value to be Converted Doesn't have the expected format 'string/email'.

    Thanks! Why would this cause the whole Calendar event to fail rather than just treating that as an invalid email?

  • ManishSolanki Profile Picture
    15,085 Super User 2025 Season 1 on at
    Re: Calendar Event Failure - Optional Invitees Runtime Value to be Converted Doesn't have the expected format 'string/email'.

    Hi @ayattaw 

     

    It was not due to semicolon at the beginning.  The semicolon ';' separator is missing in one of the input emails (highlighted below) so flow did not work:

    ;email1@location.com;;email2@location.com;email3@location.com; email3@location.com

    To make the parameter value valid, you need to separate each email by semicolon.

     

     

     

     

    If this helps & solves your problem, please remember to give a 👍 and accept my solution as it will help others in the future.

     

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