Symptom – when you open an itinerary you do not see the itinerary DSL but only the Xml (might be good news for the old school notepad coding guys) but having that experience always makes me back shiver.
When you go to tools / Extension manager
You will not see the ESB Itinerary design
What’s wrong – The VS.Net extensions are installed in the folder of the user, somehow the ESB Toolkit installer does not install the extension for all users (you can verify this by looking for the EsbExtensions in the following folder:
Solution – Close VS.Net (all instances) and go to:
‘Start\Microsoft BizTalk Server 2010 ESB Toolkit\Install Itinerary designer extension’
Open VS and then the itinerary that didn’t open, you should be able to go ahead an continue where you wanted to start!
Note, if this didn’t work, my other post on this subject might help you out.