You need to deploy the EPiServer.Templates.Alloy.Mvc.dll assembly to the bin folder for the mirroring service (typically folder MirroringService\bin under the physical site root).
The suggestion of Johan indeed fixed the error. I also needed to copy the System.Web.Optimizations.dll.
I have this same issue but I'm not using the Alloy templates. We are in the process of upgrading from version 6R2 to 7.5, and the last remaining piece is getting the mirroring to work. Since we are using the older VPP method, I created some simple classes for images and videos that inherit from MediaData, and placed them in the App_Code directory. This allows the old asset structure to work in 7.5, but it seems to cause problems with mirroring.
I get a similar error to the one Sander mentioned:
Could not create instance of content type "VideoFile" since it has an invalid .NET class associated: VideoFile, App_Code, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null
Because these classes are in the App_Code directory, there are no bin files that I can move.
I moved the classes out of the App_Code directory and into a separate project and referenced that project from the web project. I then copied the DLL to the MirroringService bin directory on both the source and target sites. However, I sitll get the exact same error message when trying to mirror content - even though the classes no longer exist in App_Code.
The problem was due to some content that was making use of the content type. Deleting the class from App_Code was not enough. The content has to be updated to use the new content type, and then the old content type has to be deleted in Admin Mode.
I'm studying EPiServer for an exam and installed EPiServer CMS 7.5, Alloy MVC template and Mirroring service on an Windows Server 2012 x64 machine.
After setting up a Mirroring channel and clicking the "Check System"-button, the following error occured:
Could not load type 'System.ServiceModel.Activation.HttpModule' from assembly 'System.ServiceModel, Version=184.108.40.206, Culture=neutral, PublicKeyToken=b77a5c561934e089'.
I've managed to solve it by modifying the web.config of the MirroringService-website to:
<add name="svcHandler" path="*.svc" verb="*" type="System.ServiceModel.Activation.ServiceHttpHandlerFactory, System.ServiceModel.Activation, Version=220.127.116.11, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
Is this a EPiServer 7.5 bug?
After solving this issue i get an error message with "Failure during export":
Could not create instance of content type "VideoFile" since it has an invalid .NET class associated: EPiServer.Templates.Alloy.Models.Media.VideoFile, EPiServer.Templates.Alloy.Mvc, Version=18.104.22.168, Culture=neutral, PublicKeyToken=null
I don't understand why this error occurs. I inspected the assembly with ILSpy to make sure the class is present.
thanks in advance,