Could not load file or assembly 'System.Web.Http, Version=5.0.0.0

Question

After installing Microsoft.Aspnet.Webapi.Webhost package to my web api project, I end up with the following exception:

Could not load file or assembly 'System.Web.Http, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

score 37 · Accepted Answer · answered Sep 12 '14 at 05:40

37

I fixed this by reinstalling the NuGet package, which corrects broken dependencies. From the package manager, run Update-Package Microsoft.AspNet.WebApi -reinstall.

answered Sep 12 '14 at 05:40

Hamid

962
3
9
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I got this problem just on IIS. Under developing environment it works Ok. – Matias Masso May 27 '22 at 20:42
This command to reinstall package did help me. ASP.NET Web API 2 (v5.2.0), Visual Studio 2022 – Viktor Fursov Mar 14 '23 at 12:15

score 3 · Answer 2 · answered Mar 10 '17 at 04:09

3

When I installed using System.Web.Http.Cors from nugget I get above error.Then I updated webApi Package to latest version.Fixed Issue.

answered Mar 10 '17 at 04:09

saktiprasad swain

340
2
8

Could not load file or assembly 'System.Web.Http, Version=5.0.0.0

2 Answers2