Forum Discussion
Data refresh error. October 2020 last version
Hi! Com error: mscorlib, An item withe the same key has already been added. Power BI Desktop and PowerBi report server last version. Source - sql server request. Merging with a table based on a que...
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