When refreshing Excel or Power BI files connected to Flowsite, you may encounter errors such as [Expression.Error], [DateFormat.Error], or similar Power Query errors. These normally appear after changes are made to the source template or when new data types are introduced.
Why These Errors Occur
1. Field or Header Name Changes
Power Query is case-sensitive and depends on exact field names.
Once a field in the Flowsite template was renamed, deleted, or replaced, the Power Query steps referencing that field will break and produce an error.
2. New or Unexpected Data Types
If a field now contains a new or unsupported data type, Power Query may not recognize or transform it properly, resulting in formatting or conversion errors.
3. Additional Fields Added
Adding new columns to a template can disrupt existing query steps, especially those that rely on fixed column positions or applied transformations.
This could also be possible to the introduction of unforeseen new type of data into the data set in which Power Query cannot recognize its format. This will need reconfiguration of Power query steps.
What to do:
If you are experienced with Power Query, you can attempt to update the query steps to resolve the issue. Some errors are caused by changing of field/header names or adding additional fields to the templates.
If one of our Flowsite support originally set this up, route the troubleshooting to us instead by reaching to our LiveChat.