It is possible that after some big code changes(i.e. a big upgrade), you might have some issues with some old dlls, and in order to prevent some unexpected problems, you might want to remove everything under your Web App's wwwroot(or any other folder), and if this is the case, then you can Kudu for Azure Web Apps;
- Login to Azure Portal with your project's Azure credentials.
- Find your Azure Web App and copy its url and write the following command to remove all items from wwwroot.
- Get-ChildItem 'D:\home\site\wwwroot' | Remove-Item -Recurse -Force
- After doing this, you shouldn't see anything under wwwroot and you can then start your clean deployment(swap for my case).