Forum Discussion
Data refresh error. October 2020 last version
I'm also encountering this same error in one of my report.
However in my research I've seen that it could potentially be caused by having 2 columns with the same name, which would be the case in your "table 6" (both user_id and week). You could try renaming both of them in the query and see if it fixes the issue.
If it ends up being the solution it's a real problem that Desktop and Report Server do not have the same behavior.
Unfortunely, the solution doesn't work. Replase query "table 6" with simple query:
SELECT user_id as user1 FROM user_barcode. The error is the same.
Hello DeclanR,
I managed to find a solution for my issue, I'm not sure if it will work for you but it's worth a try.
In short, our datasources were created with different methods (1 line vs 2 lines) even thought they connected to the same DB and when we merged them we would get this error. See this thread for a more detailed explanation: https://community.powerbi.com/t5/Report-Server/COM-error-mscorlib-An-item-with-the-same-key-has-already-been/m-p/1524902#M16968