"No default collection available" error message in BaseX

Question

I've recently reinstalled BaseX on a new laptop. When I run the same xQueries that I've run for years in BaseX, I get the following error message: "No default collection available"

As far as I can tell nothing has changed in the xQueries, or the location of any assets.

I opened the database in BaseX from a zip on my C drive, opened the xQuery and ran it as usual but it produced the error message above.

I tried unzipping the archive but that didn't work.

I looked for solution online but can't find any other mention of the same problem.

Any help would be very very gratefully received as BaseX has been an essential and reliable tool for years now and I can't really operate without it!

Thanks very much!

Akan