I have the surveys set up and am using the latest LimeSurvey version.  I set up the particpants and generated the access codes.  Now, I'm trying to send the invits out and I get Internal Servier Error: Invalid MAC and I have NO IDEA where to look to fix that. Nor I get any error messages when activating the surveys 

Any ideas where to look?

Thanks.

 

> I'm trying to send the invits out

Mail configuration
manual.limesurvey.org/Global_settings#Email_settings

I put the error message in the subject -- which is the error message i'm getting when i try to send the invites out.

I have the email configuration set correctly.

I am getting Internal Server Error: Invalid MAC when I click "Send"

What I want to know is what the heck you mean by "Invalid MAC". ..there is no where in the documentation or any explanation of why I would get that message.

That kind of information will help me figure out where to look as a starting point. I used the exact same email settings, address when I sent surveys out last year. I do not get any messages about invalid or missing configuration which is making troubleshooting this issue more difficult.

Thank you

jpowell wrote:

What I want to know is what the heck you mean by "Invalid MAC". ..there is no where in the documentation or any explanation of why I would get that message.

 

No idea, this error come from  YOUR server, not LimeSurvey.

1. Activate maildebug mode (always)
2. Try to send email
3. Copy paste all lines returned here or on a pastebin ( alt.framasoft.org/fr/framabin )

After : activate debug mode , and same test to be done.
 

We have the same issue with our Limesurvey server, since we update OS in december 2021.
The diagnostic

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Problem exist only since the last OS update, when limesurvey need to send email, from survey or from setup email (test email). It continue to exist with last limesurvey version (5.2.14). The issue is about using SSL encryption for email. Before OS update, we had setup email server with STARTTLS and address like mailserveur.dom.net and also user authentication without port address.

The solution

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Change mail serveur address from mailserveur.dom.net to mailserveur.dom.net:465 (with SSL port number).
Change encryption from StartTTLS to SSL/TLS

I don't know if this help someone, but it solve our issue.
Regards,

 

I encountered this error today, and the solution provided here wasn't particularly helpful in my case.

The issue arose because I had modified the content of the security.php file located in /application/config/security.php, which stores the database encryption keys.Due to the changed security keys, the stored email password could no longer be read from the database, resulting in the "Internal Server Error: Invalid MAC" resp. "500: Interner Serverfehler - Invalid MAC" message.

Solution: Either restore the original keys in security.php to retain your encrypted data, or simply update the email server password in the configuration.

For more information on data encryption, you can refer to the official documentation:
manual.limesurvey.org/Data_encryption