Some bytes have been replaced with the Unicode substitution character while loading file

需要修改一较旧的网页代码，当打开时，却出现异常提示：

Some bytes have been replaced with the Unicode substitution 
character while loading file 【文档路径】 with 
Unicode(UTF-8) encoding. Saving the file will not preserve the 
original file contents.

点“OK”，文档是可以打开，但是一些中文不能正常显示，如下箭头所指。

如何办？ 新建与较新的文档却没有这种情况。说明确定开发的电脑是支持UTF-8的。
不过，还是得检查电脑的设置。
打开Control Planel--> Clock and Region --> Region --> open "Administrative" tab -->
click "Change system locale..." button -->

把上面的Beta: Use Unicode UTF-8 for worldwide language support选项去选。

系统提示重启，设置才会生效。

再次打开文档，显示正常：

原文链接：Some bytes have been replaced with the Unicode substitution character while loading file