Trying to install postman in Ubuntu 16.04

I was also facing same issue.

Try this link "https://www.getpostman.com/docs/launch" and install its chrome extension and and add it extension on chrome.

Thus Postman will be installed.

For me it's worked, follow this steps

1. Download postman from [here] https://www.getpostman.com/
2. sudo rm -R /opt/Postman //remove old version if already exist.
3. sudo tar -xzf postman_file_path -C /opt
4. Open DashHome by pressing Super key
5. Search for the postman, if not found, restart the system and try 4,5 steps

Run this after running your commands:

cat > ~/.local/share/applications/postman.desktop <<EOL
[Desktop Entry]
Encoding=UTF-8
Name=Postman
Exec=postman
Icon=/opt/Postman/resources/app/assets/icon.png
Terminal=false
Type=Application
Categories=Development;
EOL