Chapter Name Excerpt Managing Projects note_element_restrictions Element names must be unique in one BPMN model. The following characters are not allowed in element names: <, >, :, ", /, \\, |, ?, * Element names must not end with a period (.). The following strings must not be used as element names: CON, PRN, AUX, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9.