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"

保存 .reg  注入注册表即可解决问题。