Octopus gives you "The path is not of a legal form"

If you are deploying something using the excellent Octopus deployment tool and you get "The path is not of a legal form" then ignore the output and check release variables.

It will look like the problem is coming from a configuration file, and some sort of path in there that can't be used. But the actual problem will be someone has set OctopusPackageDirectoryPath without a path.

So when Octopus copied the output to the new path it will fail, but not tell you it was trying to move the content.