File extension change (改变文件扩展名)
Changing a file extension may cause the file to be unrecognized by some applications.What do you want to do?
改变文件的扩展名可能会使该文件不可用.你想做什么?
Force original extension.保留原来的扩展名.
Keep extension change.继续改变扩展名.
Do not ask again. (不要再问这一问题.)