Could not load file or assembly System.Web.Http, Version=5.2.2.0

Question

I've just uploaded a Asp.Net Web Api 2.2 project to production server and I got the error stated in the title.

In my Web.config I already have this:

 <dependentAssembly>
    <assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35" culture="neutral" />
    <bindingRedirect oldVersion="0.0.0.0-5.2.2.0" newVersion="5.2.2.0" />
  </dependentAssembly>

The file does exist in the bin. What would cause this?
All my Asp.Net Web API files are up to date and show 5.2.2 as the version. It works fine on my dev machine.

Before add webapi cors pls check we.http verion (****) use first neget package PM> Install-Package Microsoft.AspNet.WebApi.Cors add webcofiq - use old correct version — K.L Sathish, Oct 31 '19 at 14:44

Mihai Dinculescu · Accepted Answer · 2016-02-19T11:04:44.097

46

Set Copy Local to true in the properties for the System.Web.Http and System.Web.Http.WebHost assemblies and redeploy the package.

If this doesn't solve your problem completely try reinstalling the NuGet package. This will hopefully correct broken dependencies. From the package management console, run this command:

Update-Package Microsoft.AspNet.WebApi -reinstall

Make sure to install System.Web.Http.WebHost as well.

edited Feb 19 '16 at 11:04

answered Dec 02 '14 at 16:29

Mihai Dinculescu

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reinstalling it did it for me. – Fabio S. Dec 17 '15 at 19:32

Daniel B · Answer 2 · 2018-08-16T12:40:20.800

12

For me, from "Solution Explorer" I checked the ver of "System.Web.Http" in the project references, which was 5.2.3.0 so, in the web.config, I changed:

<bindingRedirect oldVersion="0.0.0.0-5.2.2.0" newVersion="5.2.2.0" />

to

<bindingRedirect oldVersion="0.0.0.0-5.2.2.0" newVersion="5.2.3.0" />

then build. It worked for me!

edited Aug 16 '18 at 12:40

answered Sep 12 '15 at 16:27

Daniel B

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Look out all, this version has recently changed, so you'll need to go to 5.2.4.0 for your redirect. Otherwise this is the right answer (although I think you need to edit your old version to "0.0.0.0-5.2.3.0" in your second line. – The Senator Apr 19 '18 at 11:18
1

Saved my day! Thanks. – Sapan Ghafuri Jun 10 '18 at 13:10
This solved it for me. But there is no bindingRedirect yet. I added it and it solved it. – Alexander Feb 01 '22 at 15:46

score 4 · Answer 3 · answered May 09 '18 at 08:09

Adding below config inside web.cofig solved my issue.

  <dependentAssembly>
    <assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35" culture="neutral" />
    <bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="5.2.5.0" />
  </dependentAssembly>

score 1 · Answer 4 · answered Dec 02 '14 at 14:11

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If you have an assembly in GAC with a different version, it will always be loaded, not the one from bin folder.

answered Dec 02 '14 at 14:11

Ricardo Peres

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This is simply untrue. The dependentAssembly config he posted makes sure of that. – Mihai Dinculescu Dec 02 '14 at 16:32
That is what is not true. If you have an assembly in the GAC and another on the filesystem, same name and public key, try as you might, even loading its bytes, but you will always load the one from the GAC. Try it. – Ricardo Peres Dec 02 '14 at 16:47

score 1 · Answer 5 · answered Mar 28 '19 at 15:38

I solved the problem into the following steps:

Stopping the site into the remote web server
Cleaning the site folder
Publishing it again
Starting the site

One click publishing did not replace the correct version of dll or the remote site was keeping the file in use.

score 1 · Answer 6 · answered Dec 12 '19 at 07:16

Make sure you are referring the correct version of System.web.http in your project (check web.config).
If System.web.http is not present in reference, try to install it using nugets.
If both the above points are correct at your local then try to restore your nugets from package manager console

score 0 · Answer 7 · answered May 11 '16 at 13:42

I ran into the same exact error. It was caused by a script I was using to deploy the application which replaced the Web.config with a previous version. The Web.config was specifying the wrong version of System.Web.Http. Removing that step solved the problem.

score -1 · Answer 8 · answered Nov 24 '21 at 13:23

-1

Silly advise, but in my case restart Visual Studio helped me.

answered Nov 24 '21 at 13:23

Anton Semenov

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Trond · Answer 9 · 2015-12-05T07:18:41.377

-4

Another way to do this, which do not require a New build or update/reinstall With Nuget is to do the following in config.web:

For the dll you have issues With, do the following:

&lt;bindingRedirect oldVersion="0.0.0.0-65535.65535.65535.65535" newVersion="5.2.2.0"&gt;

I had an issue today, and this little tweak solved it...

edited Dec 05 '15 at 07:18

answered Oct 16 '15 at 21:54

Trond

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Could not load file or assembly System.Web.Http, Version=5.2.2.0

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