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Your LimeSurvey version:  LimeSurvey 5.0.3
Own server or LimeSurvey hosting: own server
Survey theme/template: Fruity
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I recently facing an issue with LimeSurvey that I'm unsure how to resolve. I had a survey with a few hundred responses, but I realized that I was missing a question and that another question was out of order. Since I can't apply these changes to an active survey, I decided to deactivate it, make the necessary adjustments, and then reactivate it.
However, i tried doing so and when importing the answers to the new survey, it says something along the lines of "failed to map the questions" and the answers wont get on the newlyactivated survey. Any ideas/fixes? Should be important to note this is my first time with limesurvey and i know basically nothing about it.
Thank You.

Whenever you deactivate a survey, responses collected so far get archived. Therefore I would always create a backup (export the responses to excel or CSV), just in case.

In theory you can reimport these archived responses when you activate the survey again. However, seems like the reordering of the questions and adding a question made it impossible for Limesurvey to remap the old structure to the new structure. Which is why you should always avoid changes after the field start. Testing and checking is essential before the field start.

If you would have an export of the responses you had collected up to the point of deactivating the survey, I would just continue the survey with the new sample and then match/map the different response tables in excel or something.

If you don't have an backup of these responses, things might get a little more complicated. I have needed to do this, so I am not sure if it is possible to export an old response table, but I don't think the GUI offers this option, so you might have to go into the database itself and export it there. For sure a lot more work than exporting a CSV or XLS file before deactivating, just in case.

Offtopic: You say you are running Limesurvey LS 5.0.3. This release (5.0.3+210609) was released on 09.06.2021, so it is now over 3 years old and hasn't received any updates, bug fixes or security patches since. You should really consider an update.

Also, LS5 is EOL since June or July, so it is not supported anymore.