Forum Discussion
Value cannot be null. Parameter name: key - Power BI Semantic Model
I had to delete each model "piece" by piece" to identify which one was causing the issue. Then I deleted that one and recreated the columns and connections.
I'm not really sure what was going on with that particular model. Hopefully someone figures it out.
I was encountering the exact same issue. This error was coming up when I was adding a new datasource. Weirdly, when I try adding this new datasource in a completely new PBI, it worked fine but when I was trying to add it in my existing PBI, kept failing with the above error of "Value Cannot be null. Parameter name Key".
The issue was for some weird reason, while adding the datasource, PBI was also adding null and query=null in the connection string (this can be seen when you open the table/dataset that you are trying to add through query editor). I did not needed it so I removed both null and query = null. Save my file. Closed Power BI and reopen Power BI and refresh and it worked! Hopefully it helps someone else who is facing similar problem.