Could not load file or assembly ‘Microsoft.ReportViewer.Common, Version=

I recently upgraded my n-tier solution from .NET 3.5 vs 2008 to 4.5 visual studio 2012. Every thing went fine apart from crystal reports and I had to install new runtime crystal reports for visual studio 2012 from the following link
After installing the above package I had to resolve some deprecated function and properties of
CrystalViewer and after that reports rendering properly in development environment (Windows 7 64 bit, SQL Server 2005, Visual Studio 2012). When I deployed the package in test environment windows server 2008 R2
the Application failed to load by throwing error
Could not load file or assembly Microsoft.ReportViewer.WebForms, Version=11

I managed to resolve ReportViewer.WebForms error by copying the DLL
from C:Program Files (x86)Microsoft Visual Studio 11.0ReportViewer to bin folder of solution and set property copylocal = true and deployed the package. After that I received the error Could not load file or assembly ‘Microsoft.ReportViewer.Common, Version= . I tried to search that DLL on my machine but couldn’t. when project is running in visual studio, In Debug-> Windows->Module the file is not listed however in global assembly cache that file is installed but I don’t know how its installed to global cache and from where . I found one solution that I had to install ReportViewer.msi from microsoft package but if i install this package it asks me to install SQL Server 2012 which I dont wan’t. Could any one help me to resolve this issue. Thanks


Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

Dont know if this is good to anyone, but search all these dlls:

  • Microsoft.ReportViewer.Common.dll
  • Microsoft.ReportViewer.ProcessingObjectModel.dll
  • Microsoft.ReportViewer.WebForms.dll
  • Microsoft.ReportViewer.WinForms.dll
  • Microsoft.ReportViewer.DataVisualization.dll

You find them in C:WindowsassemblyGAC_MSIL..., and then put them in the references of your project.

For each of them say: local copy, and check for 32 or 64 bit solution.

Method 2

You can install the Microsoft Report Viewer 2012 Runtime and change your references so they point to the ones installed by the runtime.

I have installed the runtime without it asking for SQL Server 2012. Before installing try uninstalling any previous versions of report viewer.

Method 3

As Microsoft.ReportViewer.2012.Runtime has Microsoft.ReportViewer.WebForms, Microsoft.ReportViewer.Common and Microsoft.ReportViewer.ProcessingObjectModel libraries, just run this command on PM Console:

Install-Package Microsoft.ReportViewer.2012.Runtime

Note : If you want to completely remove the old references, you can remove them from Manage NuGet Packages>Installed Packages menu and then remove the related lines from packages.config file in your project. After that it will not comeback again during building of the project.

Hope this helps…

Method 4

Could not load file or assembly ‘Microsoft.ReportViewer.Webforms’

Could not load file or assembly ‘Microsoft.ReportViewer.Common’

This issue occured for me in Visual studio 2015.


the reference for Microsoft.ReportViewer.Webforms dll is missing.

Possible Fix


To add “Microsoft.ReportViewer.Webforms.dll” to the solution.

Navigate to Nuget Package Manager Console as

“Tools–>NugetPackageManager–>Package Manager Console”.

Then enter the following command in console as below

PM>Install-Package Microsoft.ReportViewer.Runtime.WebForms

Then it will install the Reportviewer.webforms dll in “..packagesMicrosoft.ReportViewer.Runtime.WebForms.12.0.2402.15lib” (Your project folder path)

and ReportViewer.Runtime.Common dll in “..packagesMicrosoft.ReportViewer.Runtime.Common.12.0.2402.15lib”. (Your project folder path)


Remove the existing reference of “Microsoft.ReportViewer.WebForms”.
we need to refer these dll files in our Solution as “Right click Solution >References–>Add reference–>browse “.
Add both the dll files from the above paths.


Change the web.Config File to point out to Visual Studio 2015.
comment out both the Microsoft.ReportViewer.WebForms and Microsoft.ReportViewer.Common version and Uncomment both the Microsoft.ReportViewer.WebForms and Microsoft.ReportViewer.Common Version= as attached in screenshot.


Also refer the link below.

Could not load file or assembly ‘Microsoft.ReportViewer.WebForms’

Method 5

You can download the nuget package too.

Method 6

I had the same problem for Winforms.

The solution for me is:

Install-Package Microsoft.ReportViewer.Runtime.Winforms

Method 7

Simply install Microsot.ReportViewer.2012.Runtime nuget package as shown in this answer

Method 8

Add Microsot.ReportViewer 2010 or 2012 in prerequisite of setup project then it first install Report Viewer if it’s not present in “C:WindowsassemblyGAC_MSIL…” and after installing, it installs set up project

Method 9

In my case, the ‘Microsoft.ReportViewer.Common.dll’ assembly is not required for my project, so I simply removed all references (Project -> Add Reference… -> …) (all requirements from Publish tab the VS2013 removed automatically) and all works properly.

Method 10

I Had the same problem.

The solution for me is:

You must have the same version of: Microsoft.ReportViewer.ProcessingObjectModel registred in C:WindowsassemblyGAC_MSILMicrosoft.ReportViewer.ProcessingObjectModel,
like you have registraded in web.config in developer server:

enter image description here

In my case i was only registred the 13. version in my prodution server and i have the 12. version in developer server.

the solution is install the version 12. in the prodution server too

the version 12. :

Then now i have the version 12. in the prodution and the report work fine.

*** Remember to reset your IIS after instalation

enter image description here

Method 11

I resolved this problem, searching the dll’s file in C:WindowsassemblyGAC_MSIL and copied to bin directory of the proyect deployed. That work for me.

Method 12

Although rather late, but you can manually download the required DLLs from nuget at the following link:

Open the file .Rar Archive, extract the dlls and copy them manually to the bin folder of your publish.

This solution worked for me. Hope that helps !!

Method 13

I solve it by download the reportviewer.exe and install it.
After the installation, all related assemblies will be available in C:WindowsassemblyGAC_MSIL, then you can refer it in web config

All methods was sourced from or, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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