Hey @yuhuisg , thanks for your suggestion We've disabled 'Opt in' and also enabled the 'Pre Opt in Approvals' for ECID. However, this didn't work and we've received this error: It's unusual because we can see in the logs that the Marketing Cloud Visitor ID is being obtained, but setting the data ele...

@yuhuisg The work is not published to production yet, but when reviewing the network logs I could not see the mid value being sent in any of the fields. Does the ECID data element type capture the mid value for unique visitor tracking?

Thank you @yuhuisg Below are screenshots showing the data element and AA extension setup. I've set it to eVar3 as eVar1 and eVar2 are being used in a global rule for other data elements. Data Element Extension Setup

Thanks for the further clarification @yuhuisg! Unfortunately this method doesn't seem to be working when I tried to implement it, I can't see the Experience Cloud ID parameter being sent in the Analytics request. Is there a specific eVar that I should be using? Also, I can see in another example tha...

Amazing, thank you @yuhuisg   For step 2, am I correct to assume that the "Set Variable" action is to occur inside a Rule? If so, what event do you recommend to trigger this Rule, and do you recommend to treat the data as a page view when "Sending a Becon"?

Thank you for your reply!Is this directly in the Adobe Analytics extension config, or would I need to set up a new data element in Launch? 

We're looking to start tracking unique visitors using the suggested Experience Cloud ID Service.We've set this up in Launch but it appears in the network logs that only the organisation ID is being sent to the Analytics suite, and not the Experience Cloud Visitor ID.We are using the Analytics extens...