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LimeSurvey version: LimeSurvey Community Edition Version 6.17.1+260427
Own server or LimeSurvey Cloud: Own server
Survey theme/template: Bootswatch
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Is it possible to prevent LimeSurvey from sending confirmation emails to respondents who have not submitted a questionnaire, but have simply browsed the questions?

Confirmation emails are only sent when the respondents reach the final page and submit. So if they can go through until the end without answering, I currently don't see any possibility to prvento the confirmation emails. Only if you switch confirmation emails off for everyone.

Thank you so much for your prompt reply. Is there a way to instruct LimeSurvey to send confirmation email only after "Submit" has been pressed?

Afaik, confirmation emails are only sent after the submit has been pressed. If you don't reach the end of the survey and click submit, there should no confirmation email be sent.

But I usually don't use confirmations emails, so I am not 100% familiar with this.

www.limesurvey.org/manual/Participant_settings/en

Send confirmation emails
If enabled, the participant will receive a confirmation email that the survey was submitted.

According to the manual, confirmation emails should be sent on submitting a survey. Is this different for you?

Yes. Precisely. This is different than the manual. I received notifications by respondents that they received confirmation email although they did not press "Submit", but after just browsing the questionnaire.

Did you test this? Because we also get stuff from people who didn't do anything... but then actually did it.

I am also not quite sure what "just browsing the questionnaire" means? Usually, you need to click to proceed. So do they proceed through the questionnaire without giving any answers and click through it?

From what I know, Limesurvey needs to have a trigger to send the confirmation email. And that trigger would be the submit button. I don't see how a confirmation email would be send without clicking the submit button.

So did you try this and did you get confirmation emails without clicking "submit"?