I don't understand why you compare PEMSTATUS(..,5) and PEMSTATUS(..,4). The PEMSTATUS(..,5) is specificly designed to check if property exists or not and it's reflected in the help file. The PEMSTATUS(..,4) allows to check intrinisic or user defined attribute of existing properies. There's no mention in the help that it can be used for non-existing property.

>It's when the property doesn't exist that it errors. It does not return .f., it produces an error, unlike PEMSTATUS(_screen,'Printscr',5) which returns false if the property does NOT exist. I believe it is a bug because the help file states that both should return .f. if the property does not exist. You cannot use 4 to see if the property exists or not because of the error.
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