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Target Extension 2 in Launch not sending sessionId


Level 1

I'm trying to update from Target extension 1 to Target extension 2 in Launch but I keep getting these errors when I deploy the build to my dev or staging environments:

AT: request failed Error: Errors: sessionId query parameter is required;

AT: [page-init] View delivery error Error: Errors: sessionId query parameter is required;

Looking at the debugger, I see the calls to delivery do not have a value in sessionId:


If I check the first-party cookies for my domain, I see that I do have a 'mbox' cookie and it does have a value for 'session' in it. I was under the impression that at.js took care of all of this automatically (setting the cookie and pulling its value before sending requests). Am I missing something?

I also get error:

AT: request failed Error: Errors: field - [execute.mboxes] - global mbox is not allowed in mboxes.;

Which I assume is some other difference between Target 1 and Target 2 I have overlooked which may be a separate issue. I also get this entirely unhelpful error message:

AT Error unknown

5 Replies


Level 1
Also seeing this error come up now and again. Anyone have a solution?


Level 2

@reid_from_lulus  / @Michael_au: Have you tried updating the Target V2 extension recently? 


There have been a few Target V2 extension updates (some just recently) to correct bugs related to sessionID persistence issues and incorrect values generated. 


For additional details, check out the Target V2 Launch Extension release notes:


Note: I believe you need to have the ECID extension updated to at least v4.4.1 to set this up correctly. 
Hope this works — 


Level 1

Updated to the latest extension and still seeing this issue.


Console error screenshot: