更改默认安装位置C盘时,出现错误
java.lang.NullPointerException
	at sun.awt.shell.Win32ShellFolder2.access$200(Win32ShellFolder2.java:72)
	at sun.awt.shell.Win32ShellFolder2$1.call(Win32ShellFolder2.java:242)
	at sun.awt.shell.Win32ShellFolder2$1.call(Win32ShellFolder2.java:237)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at sun.awt.shell.Win32ShellFolderManager2$ComInvoker$3.run(Win32ShellFolderManager2.java:547)
	at java.lang.Thread.run(Thread.java:748)