Power Query & Data Connections

How to Fix “The preview is being determined” Stuck in Power Query Editor

The message "The preview is being determined..." appears in the Power Query Editor while the mashup…

“Expression.Error: The name ‘DateTime.LocalNow’ wasn’t recognized” (Syntax Fix)

The error "Expression.Error: The name 'DateTime.LocalNow' wasn't recognized" occurs in Power Query when the M-code interpreter…

“Unexpected Error” when Switching Power Query Environments

An "Unexpected Error" when switching Power Query environments occurs when moving queries between different runtime contexts,…

“The field ‘X’ of the record wasn’t found” during Step Expansion

The error "Expression.Error: The field '[FieldName]' of the record wasn't found" occurs in Power Query when…

Troubleshooting API Key Authentication Failures in Excel Web Queries

API key authentication failures in Power Query typically manifest as DataSource.Error: Access to the resource is…

How to Fix Power Query “Container exited unexpectedly” (Error 0x80040154)

The error "Container exited unexpectedly with code 0x80040154" occurs when Power Query’s isolated evaluation process (Microsoft.Mashup.Container.*.exe)…

“Data Source.Error: The remote name could not be resolved”

The error "Data Source.Error: The remote name could not be resolved: '[hostname]'" indicates a Domain Name…

How to Fix “Step references an unknown variable” in M-Code

The error "Expression.Error: The variable '[StepName]' is not defined" or "Step references an unknown variable" occurs…

Troubleshooting “The workbook is currently in use” during Data Refresh

The error "The workbook is currently in use" appears during a data refresh when Power Query…

Power Query “Buffer Overflow” when loading 1M+ Rows

A buffer overflow or capacity error in Power Query when handling more than one million rows…

“The authentication provider ‘Windows’ is not supported”

The error "The authentication provider 'Windows' is not supported" occurs when Power Query attempts to connect…

Troubleshooting “Evaluation ran out of memory” in the Power Query Engine

The error "Evaluation ran out of memory" indicates that Power Query’s background mashup container (Microsoft.Mashup.Container.*) exceeded…