Have you tried the View menu to open them?
Were your palettes on another monitor (Vista) and you're now working with one (Win10)?
Load one of the supplied configurations to see if that clears up things.
I haven't noticed palettes disappearing in Version 11, that's loaded onto Windows 10.
Designer, Deluxe, Expert, Basic, Platinum
RedSDK enabled, except in 2018
Windows 10, 64-bit