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Azure Data Lake refresh issue

I have my Power BI report using as source Azure Data Lake Store with no issues.

After publish the report, I can't setup refresh due error message 

You can't schedule refresh for this dataset because one or more sources currently don't support refresh.

Discover Data SourcesThis has been working before

Refresh issue

Status: Accepted
Not applicable


In my case, I am not passing an empty "second" parameter....I am just providing URL, PowerBI is creating connection string internaly.....again, if this happend, is Power BI issue that has to be fixed.


Hopefully after TWO months there are no more secondary effects when Power BI team fix an error.





Frequent Visitor

Likewise, I am also not passing an empty second parameter.


 Source = DataLake.Contents("adl://.../appinsights/processed/v2/Event/DataQuery/"),


I notice that now I cant even refresh from with PowerBI Desktop, which I used to be able to do, so for me the problem has gotten worse.PowerBI-Error-2018-08-03_11-36-21.png





Not applicable

Please.......Do you have news about this solution?


3 months waiting, and obviously paying licenses !!!!!




Regular Visitor

Hi if your getting this error when trying to connect to a data source


Unable to connect 

We encountered an error while trying to connect 

Details: "We cannot convert the value to type Logical."


To fix this follow the following steps 


Step 1. Press Cancel on the Error

Step 2. Select Get Data from the ribbon 

Step 3. Select More 

Step 4. Choose Other -> Blank Query 

Step 5. Click Connect 

Step 6. A new PowerQuery Editor will open 

Step 7. Select the view from the menu 

Step 8. Select advanced editor 

Step 9. In the advanced editor query add  ,null to  the end of your connection string previously used 


##Example - connecting to an azure data lake## 


    Source = DataLake.Contents("adl://", null)


Step 10 Click Done

Step 11 The data will now load and refresh

Not applicable

Hi lesstott

Unfortunatelly my error is in Power BI Service, I can connecto from Power Bi desktop "at the moment".


I think it will be record, 4 months after Power Bi Team broke this functionality and still waiting for the solution.


BDW, I have connection string as you are describing with "null" as last parameter.




Frequent Visitor

Unfortunately, I am still experiancing this issue. I have it working when I do a refresh through PowerBI Desktop. It will not work if I do a refresh through the PowerBI Service.


I have just downloaded the latest version of PowerBI Desktop (October 2018) and no improvement.


I have tried 3 different options for the Source string:


Source = DataLake.Contents("", [PageSize=null])


Source = DataLake.Contents("", null),



Source = DataLake.Contents(""),


The error message is always the same. (Apart from the ID's and time)

Something went wrong

There was an error when processing the data in the dataset.

Please try again later or contact support. If you contact support, please provide these details.

Message: We cannot convert the value null to type Logical. Table: Query1.

Cluster URI:

Activity ID: f5b4aa9b-4caa-435a-bbcc-19a27bbb8c86

Request ID: 20c49253-7a34-08aa-1c55-a5a99f5530d5

Time: 2018-10-18 21:32:21Z



It is interesting that some people have apparently managed to work around this issue. I just wish that I was one of them.


Having gotten used to the Azure world where I can log an issue direct with support and I get a response from MS, and we work through the issue, how do I do the same with PowerBI? I keep arriving back here. Is this it?




Frequent Visitor

I have managed to get around the problem I was having by recreating the report from scratch. It took me a couple of goes, but the new version is now refreshing on a scheduled basis.


Not applicable

jefflaw I'm afraid they don't care....after more than 4 months, the issue is still there.

I can't re-develop reports.


We are moving the "outputs" to Azure SQL with low DTU (cheapest option), to be able to run analysis,  using stored procedure to delete old data having good balance between performance/storage




Frequent Visitor

It is now January 15th of 2019, and this issue has not been fixed, still. This is making both ADLS and Power BI somewhat useless for us. We're looking into another way of doing this.

Frequent Visitor

I have been working with PowerBI Support over the last month, and I seem to have gotten around the problem that I have been having.  There were 2 things that seem to have an impact on my refresh failures.


First up, the Source statement in the Advanced Editor for the Query. Must not have a second parameter. eg

Source = DataLake.Contents("adl://"),



Source = DataLake.Contents("adl://", [PageSize=null]),


Considering it is the default when you create a new query to have [PageSize=null] as a second parameter, this is a bit annoying.


Second, was that I removed all the existing published reports that I had in my workspace, and republished. This was one of the steps that Support suggested. I am presuming that there is some caching going on, especially if you have multiple reports using the same source, as I was. 


Since then, I have not had a problem with the PowerBI Service doing a scheduled refresh.


Of course, there may have been some other changes made in the background that I am not aware of (as I mentioned, it took around a month to get this working :-))


Im not sure how feasable it is for others still having this issue to remove existing published reports from the workspace. You could try testing in a different, empty, workspace first, to see if this works for you or not.


Good luck