I've recently tried to upgrade my WebRole from Azure SDK v1.6 to v1.7. This appears to have worked OK. I can build and run the role in my devfabric just fine. When I try to deploy the upgraded project to the real cloud, the instances never start. They just sit in the "busy" state. Interestingly, they don't do the typical "recycle loop", they just sit at "busy" forever.
When I log into the instances with RDP, I see the following error in the event logs:
The application '/' belonging to site '1' has an invalid AppPoolId 'DefaultAppPool' set. Therefore, the application will be ignored.
Followed by:
Site 1 was disabled because the root application defined for the site is invalid. See the previous event log message for information about the root application is invalid.
Looking in IIS manager confirms that there is no AppPool called "DefaultAppPool". There also are none of the typical AppPools with GUIDs for names that Azure creates. Unsurprisingly, none of my sites exist either.
So how do I resolve this?