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Impactful Individual
Impactful Individual

Combobox Error

I'm adding a combo box to a canvas app and I want the datasource to be dynamics users table.  But getting this error when I select that.


One or more errors occurred. Reporting the first one: "Value cannot be null.\r\nParameter name: key"


What does this mean?




Community Support
Community Support

Hi @Mattw112IG ,

Could you describe more clearly about "dynamics users table"?

If you means that you want the combo box's data source change based on different conditions, I'm afraid it's not supported now.

For now, you could only set the combo box's data source to a fixed one.

I suggest you express your views on PowerApps Ideas Forum. Your precious feedback will be very helpful for our work.


What's more, there are so many reasons that may lead to this error.

If you could show me your combo box's Items, Fields, it will be better to help me understand your issue.




Best regards,

Community Support Team _ Phoebe Liu
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

users is a built in entity in dynamics.

I want to have a combobox or dropdown that shows the user names in it for selection.

When I try to add the entity to the PowerApp I am getting this error.




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