Layer's with "Un-defined" coordinate system: Warning or not? Displayed on the Earth or not?

[Craig_Eissler_Iceman]

When adding a layer with an un-defined coordinate system, sometimes I receive a Warning and sometimes not?

...I know how to solve this, of course, but is there any logic to if the Warning appears or not?

...In addition, sometimes the data is arbitrarily placed on the Earth somewhere in reference to other existing layers, and sometimes it is apparently in it's own space with no ability to zoom out beyond those extents. ...So, is there any logic to this as well?

Thanks,

[Craig_Eissler_Iceman · Accepted solution]

OK, well I've learned that the Unknown Coordinate System Warning ALWAYS appears in the upper-right corner of the screen. However, if you wait more than a few seconds it intentionally disappears.

I've also learned that when your data is placed on the screen with no basemap reference to compare with it is because the data coordinate extents are larger than the current Map coordinate extents. Therefore, it just sort of winds up in outer space so-to-speak.