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Bug: Datamart Loading Data Internal Error Code 500 - Failed Runtime Assertion

I was updating our datamart and was given the following Internal error message:


  • ErrorMessage: An internal error happened due to failed runtime assertion: Unable to change Model locale after other objects have been created..
  • HttpStatusCode: 500


This also occurs when I haven't updated anything in the datamart and follow path Transform Data -> Save -> Error Message

Status: Needs Info

Hi @OHMark 

Do you have this problem with all your dataflow?


Best Regards,
Community Support Team _ Ailsa Tao

Regular Visitor

Hello All!


@luizraposo is correct that the locale for me (English United Kingdom) is buggy. I switch to English United States and was able to load my datamart.

Steps to switch:

  1. Enter Datamart
  2. Trasnform Data and stay on the Home Tab
  3. Go Options -> Regional Settings
  4. Change your Locale to English United States
  5. Load Datamart - Should work

I tried switching back to English United Kingdom but it bugged out on me with the same error message. @v-yetao1-msft, Can this be resolved please as I'd prefer to stay on the English United Kingdom locale?

Frequent Visitor

Hi @OHMark , thank you for your guidance on changing the region, this solution is definitely not working for me. Are there any updates from the microsoft team @v-yetao1-msft ?

Thank you!

Regular Visitor

Thanks for the post @OHMark , the change worked for me, but in my case I changed from English United States to English Australia.


But Interested to know other solution.


Kind regards,

Regular Visitor

Hello all!


I'm in the same boat as @ivandavidbt. I've tried changing the regional settings, but still get the same error code. If anyone knows of any other solutions, that would be greatly appreciated. 


Thank you!

Regular Visitor

guys, it's in this line of OhMark that I made the configuration and it worked first hand. I suggest running variations of "English" locales to find the correct one

Regular Visitor

Hi - same problem here - are there any solutions to this?

Frequent Visitor

Thanks @OHMark , I changed from English United States to English UK and it worked.