新建记事本，输入以下内容：

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"

; 电脑 Change Extension's File Type

[HKEY_CURRENT_USER\\Software\\Classes\\.png]

@="PhotoViewer.FileAssoc.Tiff"

; Change Extension's File 电脑 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 电脑 Extension's File Type

[HKEY_CURRENT_USER\\Software\\Classes\\.ico]

@="PhotoViewer.FileAssoc.Tiff"

保存后，修改后缀为reg。双击运行