Once you've downloaded the .exe, double click on it to launch the installer wizard.
You will be prompted to the installation screen, where you can choose the destination folder for the application and whether or not Sendplus automatically runs when Windows starts.
After a successful installation you will be asked if you want to allow the application to make changes to your device. At this point, choose Yes.
Navigate to the Sendplus settings panel > Software updates and verify the version where you will be shown "Your Sendplus is up todate" like in the screenshot below:
Checking for a New Version
In order to check whether there is a new version of Sendplus you need to go to your Sendplus preferences tab. If there is a new version you will get an invitation to upgrade or postpone the action and from there follow the same process as above to install the latest version.