Orchard CMS - Errors When Pushing Changes in the Migrations Files
I really love the Orchard CMS (a CMS engine built upon the .NET MVC Framework), but it isn't without its quirks. I've found that often times, when I try to delete a column from an existing table in the migrations file, the site inexplicably starts throwing errors. After digging through the error log, I found that the error usually is along the following lines:
Error when updating module: "A tenant could not be started: Default NHibernate.PropertyNotFoundException: Could not find a getter for property '' in class ''"
Basically, even though the column was deleted in the migrations file, Orchard is still looking for that column.
The Solution
This is actually a pretty easy fix. In your App_Data folder, there is a "Sites" folder, and within that there should be a folder matching the name of your site (usually "Default"). From here, simply delete the "mappings.bin" file.
This will clear out the mappings and create new ones from scratch. From there, you should be good to go.