Get certified for free when you join Fabric Data Days 2026 and dive into Fabric, Power BI, SQL, AI, and other essential data skills.
Join nowJuly 28 - August 9 | Final Round of the Power BI Dataviz World Championships. This is your chance. Learn more
Hello,
I have a Power BI report that connects to variouys data sources (files, API) and brings them together. I made some changes yesterday, And I started getting dataformat.error's during refresh. The error is not associated with one row. Instead the whole step fails. After some backward steps to identify the issue , now I am at a stage where I am getting the error
DataFormat.Error: We couldn't convert to Number.
Details:
True
at the sorting step where I was hoping to find some problematic data...
The immediate step before refreshes fine. It s the step where I converted the values to text in order to debug if something was wrong with the data I have,,,
Any suggestions?
Thanks...
Ruchan
Well it turned out to be one of the export files had missing columns, so some columns had mismatching type of data which was failing a group by step. I am not sure that expains Power BI behaviour though...
I will now start to remove data sources one by one and see what happens. I was expecting a magic solution like "OK the cached data must have been corrupt.. Click ctrl-alt-shift refresh and see if that solves it..."
That is indeed weird. Can you provide sample data in usable format (not as a screenshot) ?
Join us in Barcelona for FabCon and SQLCon, the Fabric, Power BI, SQL, and AI community event. Save €200 with code FABCMTY200.
If you love stickers, then you will definitely want to check out our community sticker challenge, Barcelona edition!
Check out the July 2026 Power BI update to learn about new features.
| User | Count |
|---|---|
| 26 | |
| 22 | |
| 22 | |
| 20 | |
| 17 |
| User | Count |
|---|---|
| 35 | |
| 29 | |
| 21 | |
| 19 | |
| 17 |