Power Query Editor Preview: No Data loaded in All Existing Tables (? in every single table)

[PowerBIFin]

I have an existing Power BI Reports with data tables from various data sources (SQL Servers, excel files). This report is working fine, can refresh the data successfully from the Power BI Web Service and Desktop.

After the February 2021 update, I noticed that in the Power Query Editor, all tables has "?" and when I click on any single table to load the preview of the data, it just keeps loading (dots moving on top of the formula bar) and nothing happens (timed for 30 minutes and counting). This happen on every single data table which are all working. The 'Refresh' from the main Power BI Desktop window can refresh the data successfully but I just can't load the data in the Power Query Editor so I can make changes.

• I also tried adding a new table from an existing data source but it stuck in 'establishing connection'. (It can connect successfully in a New - Blank Power BI Report).
• I tried running the diagnostic but even the diagnostic table log it automatically created is stuck in loading preview.
• Tried clearing cache and increasing memory, still nothing.

Any ideas please?

[debraa]

Hi,

I have the same issue. My published reports continue to refresh but the desktop version wont load any data in Query editor. Even if I make changes in Advanced Editor and try to apply the changes, the load continues indefinitely. Even from local excel files.

I have tried downloading latest versions, clearing caches, restarting PC.

I had this a few months ago and it partially resolved itself. Sometimes its when I work from home that it suddenly works. However, the last time I had a colleague open the file and then try to edit (even though he didn't have access to the sources). He then saved it and when I re-opened it, I was able to edit the query once before it happened again.

UPDATE EDIT: this time updating to the new version seemed to work. Still had to wait 25 minutes though

[lbendlin]

Potentially. Have you considered updating to the March release?

[lbendlin]

Any merge steps in your queries?

[PowerBIFin]

There is one small table with merge step with another smaller table (1 column, with final total of ~10 rows). Will that impact the preview of all tables in the report?