Join us at FabCon Atlanta from March 16 - 20, 2026, for the ultimate Fabric, Power BI, AI and SQL community-led event. Save $200 with code FABCOMM.
Register now!The Power BI Data Visualization World Championships is back! Get ahead of the game and start preparing now! Learn more
Hi everyone,
Thanks in advance for your help. I am testing out Power BI's AutoML feature and have run into a problem when I am trying to train the model.
The error message I got was : "Expression.Error: We cannot convert the value "[Function]" to type Function".
Digger deeper in Advanced Editor, I believe the issue came from the 2nd last row.
Hi @Etsui
It seems that you're hitting the PQ firewall. In order for this to work, make sure that the privacy level for both data sources is compatible (Public/Public or Organizational/Organizational), or disable the firewall through the "Fast Combine" option.
The issue is that the firewall can't buffer certain things like functions.
You may refer to this blog to set Fast Combine options.
Best Regards,
Rico Zhou
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.
The Power BI Data Visualization World Championships is back! Get ahead of the game and start preparing now!