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Your LimeSurvey version: Version 5.4.11
Own server or LimeSurvey hosting: Own server
Survey theme/template: Own
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(Write here your question/remark)

So I am using limesurvey for a survey that has gone live. So I just realized that it shows and exports zero value (answer option 0) as missing (Missing string) for each question were I also used the decryption funktion. For questions were this function is not turned on I have my zeros. 

I have tried exporting it in several different formats but no zeros only missing values. Why on earth has it decided to do this?? I more importantly how can I recover my data. I need to know which questions have been missed and which have been answered with 0. 

Thanks in advance

It's an old issue i think.
Already fixed in newer release : update your version (5.6.44 have the fix)