Are you using Q_EED to parse the encrypted value? If you parse the encrypted value as Q_EED= RrGTT-UjVI@QwOkokSSlet.cR then it will decrypt and store the values for you accordingly.

Kindly let me know if my assumption here is correct based on the description provided

No, I didn't know about this feature. Here is the URL I am using : ${l://SurveyURL}?Verif=${m://Email1}
But how come I can't decode this encoded email afterwards? With something like this: https://www.base64decode.org/

Are you using email distribution or anonymous link?

It was an email distribution but with an anonymous link

Anyone else to help me please ?
That Q_EED element might interest me but sometimes I will retrieve encrypted emails from the url, others not.

Hi,
Apologies for not reaching out earlier, as I was out of town:

Please refer to https://www.qualtrics.com/support/survey-platform/survey-module/survey-flow/standard-elements/passing-information-through-query-strings/

It has all the details related to how we can use Q_EED and how it decodes base 64 encodings.

I am not sure why the decoding did not workout for you as I have to check it out and try out a few things in order to find the root cause