I definitely want to clear up your options for using Message+, rdp55. Message+ is not available in the Microsoft Store at the time of this writing. If the desktop version of the app is not compatible with your version of Windows, you may consider the web app. To use the web app, go here: https://www.verizon.com/solutions-and-services/apps/verizon-messages/ and select "Go to the web app". Does this help out? Did you have any other questions? 

RyanM_VZW