转到python 的安装目录，在命令行中执行：python lib/idlelib/idle.py

可以看到：
D:\Python26>python lib/idlelib/idle.py
Traceback (most recent call last):
File "lib/idlelib/idle.py", line 21, in <module>
idlelib.PyShell.main()
File "D:\Python26\lib\idlelib\PyShell.py", line 1386, in main
root = Tk(className="Idle")
File "D:\Python26\lib\lib-tk\Tkinter.py", line 1643, in __init__
self.tk = _tkinter.create(screenName, baseName, className, interactive, wantobjects, useTk, sync, use)
_tkinter.TclError: Can't find a usable init.tcl in the following directories:
{D:\usr\ov\bin} D:/Python26/lib/tcl8.5 D:/lib/tcl8.5 D:/lib/tcl8.5 D:/library D:/library D:/tcl8.5.2/library
所以修改系统变量TCL_LIBRARY 为：D:\Python26\tcl\tcl8.5 就可以了