hi there,
i know it the old question.
but it really make me crazy.

I'm using LimeSurvey CE.
but when I logging to my survey.
it's shows The CSRF token could not be verified.

what can I do to solve this problem?

Thanks

Very little information to identify any possible problem.

What is your exact LS version?
What is the server environment liken?

What means "I logg into my survey"? Surveys generally don't have a login in Limesurvey. Do you mean when you login into the Limesurvey administration? Where does the problem appear? What is the exact link?

I get the same problem with a brand new online Apache server installation.
Lime Survey 3.15.8

I could log in under Windows but not from Ubuntu in the admin page.
I always get the error message:

"

400: Mauvaise requête
The CSRF token could not be verified.
La requête ne peut pas être interprétée par le serveur à cause d’une syntaxe mal formée.Veuillez ne pas répéter la requête sans modification.
Si vous pensez qu’il s’agit d’une erreur du serveur, veuillez contacter Administrateur.

"

I try to delete cookies but it is still not working.
I also try another chromium and Firefox and get the same message on the first login.
So, it should not be a cookie problem.