Collection was modified; enumeration operation may not execute.

[Human]

Hello, 

I am having a problem when trying to load the data from Power Query into PBI Desktop for a few days already. I saw somewhere with almost the same issue where the power query editor refresh was successful but when try to load this into my PBI Desktop, it ended up showing "waiting for other queries" and then "Collection was modified; enumeration operation may not execute".

My PBI Desktop is currently running the latest version with data sources from SQL Express 2022. I've tried to follow the suggestion from the post with the same issue such as clearing the caches and even reinstall the software but the problem still happens. I really have no idea on why this happens as it never happened before. Any help or suggestion is very much appreciated.

[Anonymous]

Hi, @Human 

I am glad to help you.

You need to make sure that no other processes or queries are modifying the data while Power BI is trying to load it. This can sometimes cause the errors you see.

You can also try to simplify your Power Query steps to see if a particular transformation is causing the problem. You can load the data incrementally and check at which step the error occurs.

You mentioned that you have cleared the cache, but make sure that all caches are cleared, including the data source settings cache.

Verify that your data source settings, including privacy levels, are consistent and configured correctly.

If you're using custom code or scripts, consider using a For loop instead of an enumeration to traverse the collection.

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Fen Ling,
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[Jai-Rathinavel]

@Human , Is it refreshing in service when published ? 

Also check if the below thread helps

https://community.fabric.microsoft.com/t5/Service/Power-BI-Scheduler-Refresh-Fail-Collection-was-mod...

[Human]

@Jai-Rathinavel This happens when I want to load from Power Query into Power Desktop. I added some data and calculations on the Power Query side but before this, the loading from Query into Desktop dont have any issues.