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Your LimeSurvey version: LimeSurvey Community Edition Version 5.0.10+210723
Own server or LimeSurvey hosting: Own
Survey theme/template: default
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Sorry for posting this only now as this has been a problem for 15 months now and I still haven't found a solution. Please assist. We've had LimeSurvey for years on our own server and did the upgrades without any problems. In July of last year, I'm not sure why (NOT due to an upgrade AFAIR) surveys couldn't be submitted any longer as there's an "Invalid Signature"

500: Internal Server ErrorInvalid signatureAn internal error occurred while the Web server was processing your request.Please contact Colnect team to report this problem.

message on submission. Everything else works fine, the surveys load and can be navigated, the admin interface looks all great.


I tried to look for solutions but haven't found anything except an old bug that's stopped being reported following an upgrade. As such, I've been trying to upgrade the system without success. When prompted to do the DB upgrade from v449 to v491 I try to start

Database upgradeMake sure to make a database backup before proceeding.Please verify the following information before continuing with the database upgrade:Database type:mysqlDatabase name:limesTable prefix: Site name:SurveyRoot URL:/index.phpCurrent database version:449Target database version:491

this crashes, after a few seconds on a fast machine (meaning trying to launch some slow query), with a 500 error showing nothing (can't find anything in the PHP log), trying to restart the upgrade I then get

An non-recoverable error happened during the update. Error details:CDbCommand failed to execute the SQL statement: SQLSTATE[42S21]: Column already exists: 1060 Duplicate column name 'attributes'
File Update_450.php, line 10. Please fix this error in your database and try again

When I try to delete the now duplicate column I can try again and reach the same thing. Obviously the entire system becomes unusable as the upgrade breaks in the middle and trying to load any page gets

500: Internal Server ErrorProperty "Question.question_theme_name" is not defined.An internal error occurred while the Web server was processing your request.Please contact Colnect team to report this problem.

and so I have to restore the previous source code and DB and get back to a system that doesn't allow anyone to submit surveys. How to further pursue a solution here?

Starting to suspect each and every part of 'Update_450.php' I've eventually managed to get the DB upgrade completed after commenting out the line

updateEncryptedValues450($this->db);

and for now it seems things are finally working again but I'm left with some questions about the encryption thing going on properly or not there. How to ensure I won't be seeing any problems in the future? Should I create some new encryption key somehow? Yes, I started with a much much older version of LimeSurvey

colnect wrote:

 How to ensure I won't be seeing any problems in the future?
 

Only way would be to stay away from the encryption.

Nobody here knows in what exact state your LimeSurvey Installation is. E.g. what database is used in the backend?
So I would start to install a new test installation with the newest LS v5 build and over time move stuff to that fresh installation.
 

Thanks for answering. Could you elaborate on "stay away from encryption"? Where exactly? I don't care about encrypting the DB as these are our servers. We're with MariaDB.

Not sure about recommending a fresh installation. Is there a simple way for me to migrate all the surveys and data without this becoming a huge work? So far I've been upgrading and migrating the DB according to plan and things kept working well

And while on encryption, looking at application/config/security.php I see the encryptionnonce and encryptionsecretboxkey keys and seems I have a few versions of these values on different machines for some reason. Where are these used exactly?

colnect wrote:

 I don't care about encrypting the DB as these are our servers.
 

If that is the case, I wonder what that sentence mean?

but I'm left with some questions about the encryption thing going on properly or not there

As far I as I experienced the encryptionkeys are not only used when encrypting answers to questions (when you activate the encryption option questionwise), but also when saving credentials for the mailserver setup. If you delete the keys, you will need to save the password of the mailserver setup again. And answers of surveys might be no longer recoverable.

The concept when a encryption key is renewed, so that more and more keys are in the folder, is unknown to me.

 

While there's no need on my side for encryption, it's likely set up somewhere. Is there a link to where this is easily explained? I'm not sure what's the current situation. Thanks

As jelo already pointed out, the most likely reason is that you need to insert and save your mail server password again in global settings - after that the issue should be gone.