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Power Platform Community / Forums / Power Automate / toLower' expects its p...
Power Automate
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toLower' expects its parameter to be a string error

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Posted on by 2

First off and a heads up, I am very green with Power Automate. I hope this is okay and to avoid a bunch of screen shots, I provided the link below from a blog by Robin Hobo a Technology Specialist Cloud Endpoint working for Microsoft that shows a Power Automate Flow he developed for spam messages. I made a flow that pretty much mimics his. This Power Automate flow works great as long as the input is plain text, “I think”. A problem arises when I think the inputs start to have UTF strings in them which probably spammers are doing on purpose. Below is the error message that occurs in the BlackListLoop “condition”. e.g. toLower(triggerOutputs()?['body/From'])

I threw in some latest examples of the email Subject and From fields I think the flow chokes on. I need some way to easily purge/convert/replace this stuff out of the email Subject, Body, From or Reply-To if that is truly the problem. The error message doesn’t really help much.

 

Robin Hobo’s Power Automate Example

 

How to apply Outlook.com mail rules on the Junk Mail folder and delete email based on words saved in a txt file on OneDrive

https://robinhobo.com/how-to-apply-outlook-com-mail-rules-on-the-junk-mail-folder-and-delete-email-based-on-words-saved-in-a-txt-file-on-onedrive/

 

Error message

 

Unable to process template language expressions for action 'Condition' at line '0' and column '0': 'The template language function 'toLower' expects its parameter to be a string.

 

How to Fix Recommendation on the right (This never works)

If this error was temporary, you can try resubmitting the run and the issue may have been resolved.

 

 

Examples of email subject and from fields

From: =?UTF-8?Q?Best__S?= =?UTF-8?Q?ecurity?= =?UTF-8?Q?__Camer?= =?UTF-8?Q?a__?= <info at roman dot kalenda dot shop>

 

Subject: =?UTF-8?Q?3__Re?= =?UTF-8?Q?asons?= =?UTF-8?Q?__Eve?= =?UTF-8?Q?ryone?= =?UTF-8?Q?__Nee?= =?UTF-8?Q?ds__a?= =?UTF-8?Q?__Lig?= =?UTF-8?Q?ht__S?= =?UTF-8?Q?ocket?= =?UTF-8?Q?__Sec?= =?UTF-8?Q?urity?= =?UTF-8?Q?__Cam?= =?UTF-8?Q?era__?=

 

Let me know if I can provide anything else that would help diagnose this issue and whether or not the UTF-8 stuff above is causing this flow to break.

Thanks in advance.

 

 

 

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I have the same question (0)
  • VictorIvanidze Profile Picture
    13,079 on at

    Could you please provide a screenshot of the action where the error occurs?

  • nhraj700 Profile Picture
    2 on at

    Thank you for responding.  I have altered and refined the flow and "knock on wood" it hasn't had any issues so far. Just relying on Subject, Preview and From fields and not trying to search in email body has solved the issue.

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