Remove old unused data source

Trebor84 , One of the options is to delete all tables using those connection

also refer this

https://community.powerbi.com/t5/Desktop/Remove-the-data-source/m-p/108960/highlight/true

Hello,
If it can help I had the same problem. In the data sources windows you see the old unused data source and the one that you want to use. I only changed the unused data source path for the new data source path (used one) and the old one disappeared. Now the refresh works fine!

Good luck

HI Trebor84,

I think you need to modify your report to redirect the data source mapping to the SharePoint folder, then you can publish the new version report to power bi to replace the old data source settings.

Use OneDrive for Business links in Power BI Desktop - Power BI | Microsoft Docs

Regards,

Xiaoxin Sheng

Another reason for which you can see old data sources are unused power query transformations. It can happen if the pbix file is copied and some old Power Query transformations are left in the pbix file. 

In my case the following solution worked:

1. Open any existing power query transformation.

2. Find unused queries on the left side of Power Query editor

3. Remove unused queries

Once all unusued queries are deleted, unused data sources disappeared.  

Encountered the same problem, I changed data source from local machine folder to SharePoint, changed in Advanced query, and found old data source still shown in Data Source Setting. After changing in sample file query, the old source is disappered.

Hope it helps.