When error says "See the inner exception for more details."

Question

Errors in Power Query say "See the inner exception for more details."  How does one do this? Thanks.

Answer 1

First, a disclaimer: this is behavior which exists in preview builds to help us with debugging. It is not a supported feature of the product and may change or disappear in future releases of Power Query.
That said, to enable tracing find this registry key: [HKEY_CURRENT_USER\Software\Microsoft\Microsoft Power Query for Excel] and set TracingEnabled = 1 (REG_DWORD). You'll probably need to exit and restart Excel for the change to take effect. Log files will
be saved under the path %LOCALAPPDATA%\Microsoft\Power Query\Traces, and separate log files are written for the code running in Excel itself and for the code running in a helper process. The trace files are quite verbose, so you'll want to turn them off as
soon as you have the information you need.
But I want to stress that any place where you have a bad experience is a place where another user might have a bad experience too. We'd rather fix any problems for all users than to enable individual users to troubleshoot things on their own.