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Helper V
Helper V

PipelineException: Collection was modified; enumeration operation may not execute

Hi All,


Tonight my dataflow had this error failing its refresh after 1 hr :14 mins. Had anyone have experience with this error before?


I refreshed manually and the dataflow could be refreshed normally.


Please advise!


Thanks and best regards,


Helper V
Helper V

I would like to learn how you interprete that error message. I received 2 more today, nothing changed, just randomly received the error message.


Error: PipelineException: Collection was modified; enumeration operation may not execute. . RootActivityId = 15aae9f6-46da-42a8-b612-cb25e4631c3a.Param1 = PipelineException: Collection was modified; enumeration operation may not execute. Request ID: 4bcf7c8d-670d-42cf-8c6c-dba83bbf37d2.

Helper V
Helper V

I expect to learn away to interprete the error via its exception message. The point is the message is also vaguely describe as much as you could see from my post. 😉

Community Support
Community Support

Hi @rdnguyen,


Too little information is provided to determine the cause of the error. You can go to Refresh History to download detailed information.

Understanding and optimizing dataflows refresh - Power BI | Microsoft Docs


Or you can open a support ticket.


Best Regards

Community Support Team _ chenwu zhu


If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

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