In case we’re running an ASP.NET application on Mono using Monodevelop for the first time, we may receive the below error:
In some cases, the problem is incorrect installation of [xsp4](http://packages.ubuntu.com/precise/web/mono-xsp4) server.
Install it using:
sudo apt-get install mono-xsp4
This solved the above error.
Optional: get it from Ubuntu software center by searching for xsp4
After the xsp4 server is installed and ready. The project will start running at http://127.0.0.1:8080/
A directory access error saying [Access to the path “/etc/mono/registry” is denied](http://stackoverflow.com/q/24872394/2404470) may also show up which can be solved by simply creating the folder using [mkdir](http://alvinalexander.com/unix/edu/examples/mkdir.shtml)
sudo mkdir /etc/mono/registry
and setting the right permissions using [chmod](https://en.wikipedia.org/wiki/Chmod)
sudo chmod uog+rw /etc/mono/registry
Originally published at xameeramir.github.io.