||I have (or rather one of my users has) two datasets, both of point locations. One set has buffer regions created, and the buffers are used as the "Target feature", the other point set is used as the "Join feature". (The idea being to capture the number of points in each buffer zone.)
Some subsets do produce correct tables, but the full datasets and other subsets produce an empty table.
For the moment, we've moved to generating a "Near table" with a search radius. (Same radius as the buffer.) That should give the same results with a bit of extra work, but is a bit more effort than it should be.
Are there any known problems with Spatial Joins?