Adding query strings to personalized links

Hi, I used query strings to create embedded data with anonymous links before. Now I try to do the same with personalized links I have to provide our communication agency who executes the email blast. However, it doesn't seem to work: I tried this: https://xxxxxxxx.eu.qualtrics.com/SE?Q_DL=02J5gpoqh6nqZzT_3W6iviHrX3PFyLj_CGC_50TOg39JCE19FhX?EVT_GROUP=EL and also Q_EED: https://xxxxxxxx.eu.qualtrics.com/SE?Q_DL=02J5gpoqh6nqZzT_3W6iviHrX3PFyLj_CGC_3kD5P9pJLmvPBT7?Q_EED=eyJFVlRfR1JPVVAiPSJFTCJ9 None this works: Unable to open https://xxxxxxxx. e..... Cannot download the file information you requested. Or after putting into the browser directly: This survey is temporarily unavailable. Please try again later. (ESRVGUID|CGC_50TOg39JCE19FhX?EVT_GROUP=EL) The link without query string works fine, though So in short my question is: do query strings only work for anonymous links? Cheers, Uwe