首先，在桌面建个文本文档，然后将下面这部分内容复制进去。
Windows Registry Editor Version 5.00
; Change Extension's File Type
[HKEY_CURRENT_USER\Software\Classes\.jpg]
@="PhotoViewer.FileAssoc.Tiff"
; Change Extension's File Type
[HKEY_CURRENT_USER\Software\Classes\.jpeg]
@="PhotoViewer.FileAssoc.Tiff"
; Change Extension's File Type
[HKEY_CURRENT_USER\Software\Classes\.gif]
@="PhotoViewer.FileAssoc.Tiff"
; Change Extension's File Type
[HKEY_CURRENT_USER\Software\Classes\.png]
@="PhotoViewer.FileAssoc.Tiff"
; Change Extension's File Type
[HKEY_CURRENT_USER\Software\Classes\.bmp]
@="PhotoViewer.FileAssoc.Tiff"
; Change Extension's File Type
[HKEY_CURRENT_USER\Software\Classes\.tiff]
@="PhotoViewer.FileAssoc.Tiff"
; Change Extension's File Type
[HKEY_CURRENT_USER\Software\Classes\.ico]
@="PhotoViewer.FileAssoc.Tiff"
之后将它另存为“.reg”，也就是注册表文件，双击导入到注册表中即可。弹窗警告一律选择“是”，之后右键图片选择打开方式的时候，你会看到已经有“照片查看器”的选项了。