I've developed a Visual Web Part for Sharepoint 2010. I've used VS2010 to do that and tested the Webpart in a testing server using VS to do the deployment.
But to deploy it on the production server I had to use Powershell commands because that server doesn't have VS installed. I followed this guide to deploy it. The only problem I had was that I couldn't enable the feature via Powershell, I had to do it through the web UI (Site collection features).
Now, this Visual Web Part has a HTTP Handler that retrieves some data, this is used to load the data in the webpart asyncronously. It works perfect on the testing server, but when I access the URL of the handler on the production server I get the following:
XML Parsing Error: no element found
Line Number 1, Column 1:
I don't know how to get more information about the error. There's nothing in the source of the page, neither in the Event Log. I even added a try/catch block in the ProcessRequest method of the handler and write any exception cached to the Event Log, but doesn't seem to be triggered.
Maybe it's something related to the .ashx itself, since the catch I wrote on the .ashx.cs is not being hit.
The 'myHandler.ashx' is like this:
<%@ Assembly Name="$Sharepoint.Project.AssemblyFullName$" %>
<%@ WebHandler Language="C#" Class="MyNamespace.MyHandler" %>
But I'm not sure if the Assembly name is being replaced correctly or even replaced.