How to open Visio documents in Visio Viewer when you already have Visio installed

1. Just delete the HKEY_CLASSES_ROOT\.vsd key from you registry root
2. Enter the below registry text into a .reg file and double click to add it into your registry
3. In internet explorer choose File, Open, (select all files filter), and then select your .vsd file, and then allow the activex control to run.
4. Also to remove the warning from IE each time you open a .vsd file, set the following security option in your Internet options, Advanced dialog...
   

 

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\.vsd]
@="VisioViewer.Viewer"
"Content Type"="application/vnd.ms-visio.viewer"

[HKEY_CLASSES_ROOT\.vsd\PersistentHandler]
@="{FAEA5B46-761B-400E-B53E-E805A97A543E}"

[HKEY_CLASSES_ROOT\.vsd\shellex]

[HKEY_CLASSES_ROOT\.vsd\shellex\{8895b1c6-b41f-4c1c-a562-0d564250836f}]
@="{21E17C2F-AD3A-4b89-841F-09CFE02D16B7}"