Unable to start application on this device: an unknown server-side (Windows)

Hi @Chris_Trevarthen
have now downgraded to Appium 1.8.1 but get an error that suggests I still have an Appium problem.
(it’r error referenced here by someone else: java.lang.ClassCastException: java.util.HashMap cannot be cast to org.openqa.selenium.WebElement ie error includes “java.lang.ClassCastException: java.util.HashMap cannot be cast to org.openqa.selenium.WebElement)”) .

I downloaded Appium Desktop 1.8.1 - this is what it says in Control panel and ‘About Appium’.
If I actually click ‘Appium’ to start that application though, I see a screen offering option ‘Start Server 1.9.1’.
Can anyone tell me whether Server is supposed to have a different version number or is this an Appium version control mistake?
Regards
Dan