Could not load file or assembly ... The parameter is incorrect


Recently I met the following exception at C# solution:

Error 2 Could not load file or assembly 'Newtonsoft.Json, Version=, Culture=neutral, PublicKeyToken=b9a188c8922137c6' or one of its dependencies. The parameter is incorrect. (Exception from HRESULT: 0x80070057 (E_INVALIDARG))

This does not depend either on my code or on the name of assembly (like Newtonsoft.Json in this case).

When I delete this dll from the solution the compiler tells about another in the same exception. So I suppose something shoud be turned off/on at my PC :)

asked on Stack Overflow Nov 25, 2011 by Liker777 • edited Nov 25, 2011 by Otiel

27 Answers


Looks like a corrupted assembly being referenced.

Clear both:

  1. the \bin folder of your project

  2. the temp folder (should be C:\Users\your_username\AppData\Local\Temp\Temporary ASP.NET Files in windows 7)

and see if the error still happens

answered on Stack Overflow Nov 25, 2011 by Alex

Depending on if your are running X64 you might need to clean up a couple more spots. Just cleaning up my user directory was not enough.

  1. %TEMP%\Temporary ASP.NET Files
  2. C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files
  3. C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files
  4. C:\Windows\Microsoft.NET\Framework64\v2.0.50727\Temporary ASP.NET Files
  5. C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files

This list will grow as if you have other versions of the framework installed.

answered on Stack Overflow Jul 31, 2012 by Thomas

I had to clear

C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files

Only then did the issue get resolved.

answered on Stack Overflow Apr 16, 2013 by Sachin Kainth

To know what to clear for sure - add the following registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Fusion\EnableLog (DWord set to 1).

Then you will see output like below. This tells you where is attempting to load your DLLs. Clear this directory.

LOG: This bind starts in default load context.
LOG: Using application configuration file: c:\app\AtlasAdvisor\web\web.config
LOG: Using host configuration file: C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet.config
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\v4.0.30319\config\machine.config.
LOG: Policy not being applied to reference at this time (private, custom, partial, or location-based assembly bind).
LOG: Attempting download of new URL **file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/3c8629f7/dfa387b6/Avanade.ViddlerNet.DLL.**
LOG: Attempting download of new URL **file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files/root/3c8629f7/dfa387b6/Avanade.ViddlerNet/Avanade.ViddlerNet.DLL**.
answered on Stack Overflow Dec 8, 2013 by voidsstr • edited Mar 7, 2016 by Yakk - Adam Nevraumont

Clear out the temporary framework files for your project in:-

C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files\

answered on Stack Overflow Jun 14, 2012 by andy

You can also clear the packages directory and allow NuGet to re-download missing packages

it solved the issue for me

answered on Stack Overflow May 5, 2014 by megz

Delete all files from these folders .

C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files C:/Windows/Microsoft.NET/Framework64/v4.0.30319/Temporary ASP.NET Files

answered on Stack Overflow Oct 2, 2015 by Rakin

Getting fresh set of binaries from Source control helped.


answered on Stack Overflow Apr 23, 2012 by Asif

Just clear this folder: (only windows x64)

C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files

answered on Stack Overflow Jul 27, 2015 by pixparker

Thanks Alex your second point helped me fix this.

It appears that unless you run visual studio as an administrator in Windows 7 it stores your temp files locally rather than C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files.

See following blog post:

answered on Stack Overflow Nov 20, 2012 by Ant

I had the same issue here - above solutions didn't work. Problem was with ActionMailer. I ran the following uninstall and install nuget commands

uninstall-package ActionMailer
install-package ActionMailer

Resolved my problems, hopefully will help someone else.

answered on Stack Overflow Mar 27, 2013 by LiamB

This can happen while referencing COM wrapper dlls. Within your Visual Studio Project, under References, select the COM wrapper dlls being referenced and ensure they have the the following property values: "Embed Interop Types": False and "Specific Version": False.

answered on Stack Overflow Jun 10, 2014 by Nemo

I just delete my application temp data from this path

C:/Windows/Microsoft.NET/Framework/v4.0.30319/Temporary ASP.NET Files

Problem resolve

answered on Stack Overflow Apr 8, 2015 by atik sarker • edited Apr 8, 2015 by atik sarker

I see lot of techies have posted about clearing temporary directories of ASP .Net run-time pertaining to each and every .Net framework hosted on your machine as in this answer. But I believe we should know the clear-cut logistics as to why we need to blindly clear all of temporary working directories of all .Net frameworks. According to me, it should not be the case.

My advice would be that you should try a pin pointed directory clearing approach to resolve this issue. How would you know which directory to clear?

  1. Go to IIS and right click on your website node in left navigation pane to open the context menu. In the context menu point to Manage Application -> Advanced Settings... to open the Advanced Settings window.
  2. Check the Application Pool your website is assigned to. In my case it is DefaultAppPool as shown below:

enter image description here

  1. Now go to Application Pools node in left navigation bar in the IIS. Now check that which .Net CLR Version is being run by your app pool. In my case it is v4.0 as shown below:

enter image description here

Since the CLR version being hosted by my app pool is v4.0, so I prcisely cleared only the temporary files in the folder pertaining to ASP .NET v4.0 only as below:

C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Temporary ASP.NET Files

And that's it. My problem got resolved.

Lesson learnt: This is indicative of the fact that all the temporary files being used by your website aren't scattered across several directories but they are at once place being referred by your app pool. So you need to clear that specific folder only.

answered on Stack Overflow Jul 25, 2017 by RBT • edited Jul 26, 2017 by RBT

Clearing C:\Windows\Microsoft.NET\Framework\v2.0.50727\Temporary ASP.NET Files worked for me. Thinking of automating the deletion process to avoid the issue in future.

answered on Stack Overflow Aug 16, 2012 by stephen ebichondo

If you are using SQL Server 2012's Data Tools, which uses the VS2010 shell as at May 1 2013, check your Configuration Manager settings. A server name change from Workflow to xCPWorkflow was enough to produce the exact same The parameter is incorrect (Exception from HRESULT: 0x80070057 (E_INVALIDARG)) message.

answered on Stack Overflow May 2, 2013 by SAinCA

You can either clean, build or rebuild your application or simply delete Temporary ASP.NET Files at C:\Users\YOUR USERNAME\AppData\Local\Temp

This works like magic. In my case i had an assembly binding issue saying Could not load file bla bla bla

you can also see solution 2 as

answered on Stack Overflow Jun 14, 2015 by Ifeanyi Chukwu

I had this problem when making controller in MVC. I changed version .net framework. The problem was solved

answered on Stack Overflow Sep 16, 2017 by Hossein Hajizadeh • edited Sep 16, 2017 by Hossein Hajizadeh

The problem relates to the .Net runtime version of a referenced class library (expaned references, select the library and check the "Runtime Version". I had a problem with Antlr3.Runtime, after upgrading my visual studio project to v4.5. I used NuGet to uninstall Microsoft ASP.NET Web Optimisation Framework (due to a chain of dependencies that prevented me from uninstalling Antlr3 directly)

I then used NuGet to reinstall the Microsoft ASP.NET Web Optimisation Framework. This reinstalled the correct runtime versions.

answered on Stack Overflow Aug 10, 2013 by Dave Russell

In my case i wanted to compile a COM visible DLL. The problem was that an older version of this DLL was located here:

C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE

Thus Visual Studio loaded this version instead of the newly compiled one, as it tried to register it.

answered on Stack Overflow Nov 14, 2013 by dummy

Clear all files from temporary folder (C:\Users\user_name\AppData\Local\Temp\Temporary ASP.NET Files\project folder)

answered on Stack Overflow Mar 10, 2014 by Kaushal

Sometimes you, also, need to clean this folder: C:\Windows\Temp\Temporary ASP.NET

answered on Stack Overflow May 12, 2014 by Eriendel

I faced same error because application didn't find dependent frameworks in C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\ folder. I just repair my Visual studio which added required framework in above location and it working fine.

answered on Stack Overflow Oct 12, 2015 by AirCodeOne

In my case, changing the IISExpress port number in my project properties, solved the problem.

answered on Stack Overflow Jan 29, 2016 by h3n

If anyone else out there is using the WiX toolset, I discovered that my installer project had a reference to an old project that had recently been removed from the solution. Took me a while to realize since there are a number of projects in the solution I was attempting to build and the message did not indicate which project was failing to build (and clean, which was failing as well).

answered on Stack Overflow Nov 22, 2016 by rusty

I had users of Siemens Teamcenter 10 Client for Microsoft Office getting the same error about a different DLL. None of the other answers worked. The solution was to delete the folders in

answered on Stack Overflow Nov 23, 2016 by Caleb Mauer

I Had the similar issue while opening Nuget Packet manager, I removed all the temp files and build the project, it worked fine.

answered on Stack Overflow Jan 27, 2020 by Shreya Singh

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