Setting up windbg for debugging Windows Developer - keymanapp/keyman GitHub Wiki
A sensible default for Symbol Search Path:
srv*c:\symbols\km*https://downloads.keyman.com/windows/symbols;srv*c:\symbols\ms*https://msdl.microsoft.com/download/symbols
Note: some versions of windbg require paths to be semicolon separated
You may also want to consider adding your local build symbols:
c:\projects\keyman\app\windows\debug\desktop
c:\projects\keyman\app\windows\debug\engine
c:\projects\keyman\app\developer\debug