This file uses multiple data sources

How the message appears

Copied exactly from each source. A name in square brackets replaced one from someone else's project.

Potential security risk
This file uses multiple data sources. Information in one data source might be shared with other data sources without your knowledge. Only open this file if you trust the sender. Do you want to open this file?

This file uses multiple data sources. Information in one data source might be shared with other data sources without your knowledge.

What causes it

1. 1

   The file reads from more than one source

   Microsoft's page on composite models says Desktop shows a warning the first time it opens a file with more than one source. The reason it gives: a query sent to one source can include values read from another, and an admin of that source can see them in its logs. Our project reads SQL Server, a web API and an Excel file, and Desktop asked on first open. The quoted README says the same of its projects, and that OK is safe for them.

   Source: Use composite models in Power BI Desktop[3], mscottsewell/DataverseToPowerBI[2], Power BI Desktop 2.159.883.0, Studio fixture F12[1].

   Out of reachThe Report Doctor can't detect this, because the files are not broken, and the question is about whether you trust them.
2. 2

   It is a fresh copy, so Desktop asks again

   Desktop asked on every fresh copy of our project, including a copy of its own save that no other tool had touched. After we clicked OK and saved, it did not ask again for that copy. So the answer stays with that copy. A fresh copy, such as a new zip, has no answer yet, and Desktop asks once more.

   Source: Power BI Desktop 2.159.883.0, Studio fixture F12[1].

   Out of reachThe Report Doctor can't detect this, because the answer Desktop keeps is not in the definition files the Report Doctor reads.

The fix

If the project is yours, or you trust whoever sent it, click OK. If you do not know where it came from, click Cancel and read its sources first. In a PBIP project they are in the TMDL files of the semantic model: expressions.tmdl and each table file.

In expressions.tmdl:

Source = Sql.Database(SqlServer, "WideWorldImporters"),
Source = Csv.Document(Web.Contents("https://data-api.ecb.europa.eu")),
Source = Excel.Workbook(File.Contents(BudgetPath), null, true),

Source = Sql.Database(SqlServer, "WideWorldImporters"),

Our project reads three kinds of source, and Desktop asked on first open. You do not need to remove one. Click OK if you trust the file.

The Power BI Report Doctor cannot find this. Nothing in the files is broken, so there is nothing to find.

For the other messages a project can stop on, listed by the file that causes each, see Power BI Desktop can't open a PBIP.

Worth knowing

• Microsoft says the warning is similar to the one Desktop shows for a file that contains native SQL queries.

Sources

• [1]Desktop run: Power BI Desktop 2.159.883.0, Studio fixture F12. Our run on Wide World Importers open data: we opened fresh copies of the project, one of them a copy of Desktop's own save with no other tool involved. The message is typed from our screenshot. Seen 2026-10-28.
• [2]GitHub repository: mscottsewell/DataverseToPowerBI. The README, "Security Warning on First Open". Read 2026-11-01.
• [3]Microsoft Learn: Use composite models in Power BI Desktop. The section "Security implications". Read 2026-11-01.