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Your LimeSurvey version: Version 3.23.7+201006
Own server or LimeSurvey hosting: Own server
Survey theme/template:
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Hi,
is it possible to update a previous response? I know how to display the response in an quation type with {questionid} or {questionid.value}. I would like to edit the value of a previous question (to be precide is would liek to delete it, i.e. update it to ""). How can I achieve this?
Thanks!

Use a question of type "equation" with an assignment, like
{Q1=""} or {Q1_SQ001=""} (depends on the question type)
at the end of the survey.

Thanks!
I tried {Q1.value=''} which was a close miss.

.value only refers to the assessment value of a question, if you don't use assessment values, this won't work.