What is .XER file extension?
Project planning file created by Primavera P6, a project planning application; saves the tasks, timeline, materials, and other resources required for the project; enables a project manager to plan and track progress.
Primavera P6 was developed by Oracle after they acquired Primavera Systems, the creators of Primavera P3 (a predecessor to P6). P3 projects use the .P3 extension and can be imported using P6 by selecting File ? Import from the application menu.
You can see a list of software programs here on easyfileopener.org that can open this file type so that you don’t need to search for it on the web. You can then open your file with this extension using a software listed below.