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Your LimeSurvey version: Version 5.6.8+230227
Own server or LimeSurvey hosting: own server
Survey theme/template: default
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I'm trying to verify my users email address before letting them continue the survey.  They have a token (their user ID) and i've added their address as Attribute_2.  Currently if they input the wrong address it just allows them to continue but does not display any questions.  I'd like to be able to check or verify the address before allowing them to continue at all.  Is that possible? 

You can use in Question validation equation but then : the email are shown in the javascript code … (user can check source)

Another solution with quota maybe ?
1. Add a Yes/No question in a second group, set this question hidden
2. Set default value to Y with {if(Q00.NAOK == TOKEN:ATTRIBUTE_2,"Y","N")}
3. Set a quota to this question at 0 for N

 

Perfect! That's exactly what I needed. I was really overcomplicating things.