This article is from the Apple II GNO FAQ, by Devin Reade with numerous contributions by others.
A#14.1: You need to set the auxiliary file type of the program in question to $DC00. Use the chtyp command: chtyp -a \$DC00 ProgramName Note the '\' character; it must be there to escape the '$' character from the shell, otherwise the $DC00 would be treated as a shell variable. Also note that this fix will not work if the program's file type is S16 and the file resides on an HFS volume. (An EXE file on an HFS volume should be fine.)
 
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