Once I have that context, I can give you a better idea of what it is.
A shared, secure container for sensitive collaborative data, requiring a password to open. Typical Steps for Handling a .7z File Teamwork.7z
A compressed folder containing documents, photos, or presentations related to a corporate or academic teamwork project. Once I have that context, I can give
Download and install the free 7-Zip software to extract the contents. Once I have that context
A compressed package containing specialized assets for a team-based gaming mod, software application, or digital collaborative tool.
To provide a more detailed write-up, I need to know the context of the file: did you encounter or download "Teamwork.7z"?