smass.exe is a Tumbleweed Desktop Validator Core that belongs to Tumbleweed Desktop Validator from Tumbleweed Communications. It should be installed on your computer as well as you install the software on the computer. Smass.exe is not malicious related, But it will be a very frustrated thing for users to get the smass.exe error messages while using the computer and fail to run the computer or launch some specific programs correctly.