Telerik.Reporting.Report exists in both ....

[Dave]

I've recently joined a team that uses several Telerik Controls.  In trying to complile the solution i'm getting the following error ....

Error 110 The type 'Telerik.Reporting.Report' exists in both 'c:\Windows\assembly\GAC_MSIL\Telerik.Reporting\4.2.10.1110__a9d7983dfcc261be\Telerik.Reporting.dll' and 'c:\Users\dlburlin\AppData\Local\Temp\Temporary ASP.NET Files\ccams portal\63c8d154\7e485bda\assembly\dl3\cff3d571\00671892_66a1cb01\Telerik.Reporting.DLL' C:\Users\dlburlin\Documents\Visual Studio 2010\Projects\cCAMS\Web Application\DEV\cCAMSv2\cCAMS Portal\Reports\BackupInventoryReport.aspx.cs 53 27 C:\...\cCAMS Portal\

i've tried deleting the Temporary ASP.NET files folder but of course its recreated.

Any pointers on what's going on here would be much apprecaited!

regards
Dave

p.s. Using Visual Studio 2010/ .NET framework 4.x

[Chavdar]

Hi Dave,

This is a generic error and usually means that there is a mismatch in your referenced assemblies and the actual ones used. Most likely you have side-by-side reporting installations and have mismatched references. Please use the Upgrade Wizard to upgrade your projects containing Telerik reports and rebuild them. If you have added manual references i.e. Copy Local = True, then delete all assemblies from the \bin folder, re-add proper references in the project and rebuild the project after that. If the problem still occurs make sure that you have specified the full assembly qualified name in each reference. For example:

<%@ Register assembly="Telerik.ReportViewer.WebForms, Version=5.0.11.328, Culture=neutral, PublicKeyToken=a9d7983dfcc261be" namespace="Telerik.ReportViewer.WebForms" tagprefix="telerik" %>

as opposed to:

<%@ Register TagPrefix="telerik" Assembly="Telerik.ReportViewer.WebForms" Namespace="Telerik.ReportViewer.WebForms" %>

Hope this helps.

Regards,
Chavdar
the Telerik team

[Rick]

I seem to have this problem continuously with Telerik Reporting. Very often when I have to move my development environment from one machine to another, such as to my laptop or another development machine, the error crops up again.

I want to reference all of my DLLs in the web\bin folder to make deployment easier, so I made sure that every reference to Telerik Reporting in my project points to the DLL that I have copied into there, rather than the installed version or the GAC.

Recently, I found that there was a later version of the reporting component available, so I installed it and copied the new DLL into the Web/Bin folder. The new Telerik release resulted in one compilation error message that I fixed by adding a cast to Telerik.Reporting.IReportDocument.

Now when I try to rebuild, I get the message:

Error 237 The type 'Telerik.Reporting.IReportDocument' exists in both 'C:\Program Files\Telerik\Reporting Q2 2011\bin\Telerik.Reporting.dll' and 'D:\Data\Development\mywebprojectdir\Code\Web\Bin\Telerik.Reporting.dll'.

I keep going through all of my project references, I but I don't see anywhere where I am referencing the dll in the C:\Program Files... folder. In fact, I can only find one reference to the dll, in the Web/Bin folder. If I delete that reference, it is just automatically added back in the next time I compile.

I did not use a upgrade wizard after installing Telerik Reporting because I do not see one in the Telerik install folders.

How do I go about debugging this and hopefully setting up my project so that it can be built on any machine after restoring the files from a source code repository? I'm currently using Git, but I was previously using SubVersion and had the same problem.

I'm not sure at this point, but I think I have gotten this to work in the past by referencing the installed version, but this is not ideal because it requires that I install Telerik Reporting on all machines that I want to build on, even the production server.

Rick

[Peter]

Hi Rick,

The Upgrade Wizard can be started from Visual Studio's Telerik Reporting Menu. When manually upgrading, updating the references/assemblies is not enough. Check out the Upgrading to a Newer Version of Telerik Reporting help article that elaborates on the required changes.

Generally the report designer requires the Telerik Reporting assemblies to be available in GAC. Thus keeping the assemblies in the \bin folder is only recommended for deploying.

You may find useful How the Runtime Locates Assemblies MSDN article and Deploying Applications using Telerik Reporting help article.

All the best,
Peter
the Telerik team