ECP files are associated with Esri’s Geographic Information System software products. Esri Authoring/License files use the .ecp extension. ECP files also relate to the Ettercap network analysis program. Ettercap intercepts network traffic for security testing. The easyC programming software saves projects as .ecp files. easyC teaches basic programming and robotics. Advanced easyC users can program in C language. The EasyC Project Format and easyC software come from Intelitek. ECP files may be used by other programs too. To open .ecp files, you need the program that created them. Check ECP files for viruses. Update the program if it cannot open its ECP files.