By default all \wwwroot folders are already configured as application directories. This allows your asp.net applications to run from \wwwroot\bin.
But if you try to run a asp.net application from a sub-folder ie: \wwwroot\testapp1\bin, this application will likely fail because the \testasp1 directory is not setup as a application/virtual directory.
To make a sub-folder a application/virtual directory, follow these steps:
1. goto the Helm control panel and find your domain.
2. Then goto the 'Virtual Directories' icon and then click add new
3. enter the name of your sub-folder in the Virtual Directory Name textbox ie: testapp1
4. select the Physical Folder and click ok. You should see \testapp1
5. click save
Assuming that the directory \wwwroot\testapp1 already was created, this example would make the \wwwroot\testapp1 folder a application/virtual directory and allow asp.net applications to run from the new \wwwroot\testapp1\bin directory.