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Your LimeSurvey version: 6.4.2
Own server or LimeSurvey hosting: Own server
Survey theme/template: customized
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Hi,
Yestarday I updated my Limesurvey instalation to 6.4.2 version. Today I'm trying to download the answer of my questionaries but I can't access the "Registers" ("Registros" in Portuguese) menu item. When I click in this option it starts running but do nothing.
Please, if you have any ideia to solve this problem, please, help me!
Best regards,
Eduardo Folly.

I don't have this menu in core LimeSurey.
Came from a plugin ?

Else :
Right click : open in a new tab : you have the basic error
set debug in config.php [url] manual.limesurvey.org/Debug_mode [/url]
Right click : open in a new tab : you have the complete error

I don't have this menu in core LimeSurey.

I bet you have. It is the "Responses" item in English.

Yes, "Responses" is much better. I think the portugueses (pt-br) translation was not so good.

I did what DenisChenu suggested and this is the error message: "Internal Server Error - Invalid MAC".

Any suggestion?

Attached the complete error. 

www.vivo.com.br/para-empresas/produtos-e...ais/vivo-voz-negocio

As Limesurvey is open source, you can help with improving the translations by accessing translate.limesurvey.org. The credentials are the same as for the forum. We are always happy to have help.

Unfortunately, there are very few contributors for PT-BR. It would be good to have a few more natives. My Portugues is pretty good I think, but I am a "gringo" and not native.

PT-BR is 95% translated for LS 6, which is OK. But PT-PT is at 99%. We can't be beaten by the Portuguese, can we? Also a lot of the suggestions for PT-BR come from Samarta from PT-PT (A big Thank you to @samarta). But it is "vergonhoso" that the few Portuguese beat 220 million Brazilians.

I'm sorry, I was not telling the translation is bad. My english do not allowed me to say what I want, than when you use "Response" I said it's much better than the word that I used.
I'm new in this community and I can help translating to portuguese (pt-br). As I said, my english is not so good, but I can try to help.
Again, I'm sorry!

Don't worry. There is nothing wrong with saying that a translation is bad, it happens. Sometimes I look at translations I did years ago and wonder what I was thinking.

But I understand now that your comment was referring to "Registers" which is a viable translation for "Registros", but here I am not sure if "Registros" is actually the best translation for "Responses". I think "Respostas" or even "Resultados" would be better. "Registros" isn't completely out of this world and one can guess what would be behind this item, but it is surely not intuitive, I think.

In anyway, every little help that we can get with the translations is very well appreciated. We are currently only missing only 5%.

Ok, I will start translating!

Coming back to the issue, I found what happened: I installed Limesurvey using Sotfaculous and update too.
I don't know why, but it create a new data base with another cryptokeys. When I converted the stage to live, it made a confusion with the keys and the data base. Maybe I made something wrong. The error message was about the difference of the cryptokeys.
I had to rollback the instalation and I lost some records. But now it's working.
Thanks a lot for all of you. I just could identify the problem because you help me.
Best regards.

Stay away from softalicoius and software alike. You never know what modifications they do to limesurvey. Limesurvey is so easy to install nowadays that things like softalicoius aren't rally necessary anymore. I would always try to keep my software mint and clean.