Non null assertion failure when performing a refresh

[roger-allen]

Hi

I am seeing this error

Non-null assertion failure: resource: Resource should be available for query CPU to store FoldedArtifacts in cache

I have tried this in both Power BI desktop and the version Power BI desktop in the MS store - no difference.

I get the error every time I 'refresh' data, though invidual queries work fine. All the queries are against SQL developer on the same laptop. If I delete the query 'CPU' I get the same error but for a different query so  it appears that the issue is with the location of the FoldedArtifacts cache rather than any particular query.

I've tried deleting the contents of C:\Users\redge\Microsoft\Power BI Desktop Store App\FoldedArtifactsCache but that doesn't seem to make any difference

Disk, CPU and memory are not an issue

Thanks

Roger

[roger-allen]

FYI, Microsoft confirmed it as a bug and issued a new version 2.147.931.0 on 15th September 2025, which resolved the issue

[v-sdhruv]

Hi @roger-allen ,

Thanks for sharing the update here. I am sure the other community members facing the same issue would benefit from it.
Thank you for reaching out and using Microsoft Community Forum

[roger-allen]

Just to keep you updated. I've heard back from Microsoft and between us we have confirmed that the issue lieswith the new August update. As a work around I have gone back to the July update, which does not have the issue

[roger-allen]

Thanks. I've opened a ticket. In the meantime I've learnt that if you export the file as a pbit file and rename to a .zip then it makes the contents readable. I'm currently running the contents of those files through AI to see if it can work out what the problem is

[v-sdhruv · Accepted solution]

Hi @roger-allen ,

You can use this link to create a Support ticket-
Microsoft Fabric service status
Hope this helps!

[FBergamaschi]

Never seen this error

Suggest to open a supporto ticket

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Francesco Bergamaschi

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