Power BI | Access data source - doesn't show all the queries

I have no explanation, but I have resolved my issue.  After narrowing it down to the Union Query and unable to identify any reason why that was causing a problem, I used the Union Query to make a table.  Then I was able to reference the newly created table (output of the Union Query) rather than the Union Query itself and the original query that disappeared magically reappeared in PowerBI.

I had used almost an identical process with a Union Query previously with no issues with visibility in PowerBI - the only difference is that in the recent example the Union Query returned many more rows than the previous.  So maybe it was some sort of internal memory thing to execute all the related queries.

Whatever the cause...now I can at least move on with my life...

There are certain queries and functions that when used in Access renders the query unviewable/useable in PowerBI although I've never found a definitive list of what is not compatible.  I recently modified a query and it is no longer viewable in PowerBI, but I'm still troubleshooting to figure out exactly what it doesn't like (was looking on the Community for some inspiration when I came across your post).  Thus far I have figured out that removing reference to a Union Query makes it reappear in PowerBI (but I have at least one other query that references a Union Query so that in and of itself is not the issue).  My suggestion is to follow a "trial and error" approach (copy the query and remove different components - fields using formulas, references to other queries, etc.) until you can narrow down the issue.

Good luck. :)

Thanks for your replies Rich_P & v-jiascu-msftbut i dont use the NZ() and Plaintext function.

Rich_P, one of all the missing queries was using the NZ() function and their were linked to each other. Thanks for your help :-)

Problem solved.

Bless you! I spent a whole week trying to figure this out!!