I used the following code to get the path
Path errorFilePath = FileSystems.getDefault().getPath(errorFile);
When I try to move
To be sure to get the right path on Windows or Linux on any drive letter, you could do something like this:
path = path.replaceFirst("^/(.:/)", "$1");
That says: If the beginning of the string is a slash, then a character, then a colon and another slash, replace it with the character, the colon, and the slash (leaving the leading slash off).
If you're on Linux, you shouldn't end up with a colon in your path, and there won't be a match. If you are on Windows, this should work for any drive letter.