Do you have .net 4.5 installed on your local machine? How did you install Umbraco, just unzipping it or using nuget maybe?

Yes. I'm working on windows 8.1 and also i installed asp.net 4.5 with Web PI. I just unzipped.

Alright, great! Could you try to run fiddler while you're trying to log in and see what the actual error is you're getting back from the server? You might be able to expand the 500 error in chrome as well.

I'm only interested in the calls to PostLogin that give a 500 error, there's something strange going on there. :)

I get this error on fiddler

{"Message":"An error has occurred.","ExceptionMessage":"The user 'admin' could not be found in the Umbraco database","ExceptionType":"System.InvalidOperationException","StackTrace":"   konum: Umbraco.Web.Security.WebSecurity.GetBackOfficeUser(String username)\r\n   konum: Umbraco.Web.Editors.AuthenticationController.PostLogin(LoginModel loginModel)\r\n   konum: lambda_method(Closure , Object , Object[] )\r\n   konum: System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.<>c__DisplayClass13.<GetExecutor>b__c(Object instance, Object[] methodParameters)\r\n   konum: System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.Execute(Object instance, Object[] arguments)\r\n   konum: System.Web.Http.Controllers.ReflectedHttpActionDescriptor.<>c__DisplayClass5.<ExecuteAsync>b__4()\r\n   konum: System.Threading.Tasks.TaskHelpers.RunSynchronously[TResult](Func`1 func, CancellationToken cancellationToken)"}

But I get invalid user name or password error when i try a false username on login page.

Okay, well I think the error says enough, The user 'admin' could not be found in the Umbraco database. Any idea why that might be?

The installation went without error, sqlce database started and admin user created. well i dont know why the site do this. The txt starter kit running correct also.

I've just retried to clean install and realize that umbraco gives The ValueType does not match a known value typeerror. just once. i refreshed the page and login page showed up.

Yess. I knew it. Thank you so much. :)

I'm getting the same error on 7.1.7 (in US), it's very intermittent (logins work fine one day, then just stop). Chrome Dev console shows the error as "POST https://www.nwcouncil.org/umbraco/backoffice/UmbracoApi/Authentication/PostLogin 500 (Internal Server Error) DependencyHandler.axd?s=L3VtYnJhY28vbGliL2pxdWVyeS9qcXVlcnktMi4wLjMubWluLmpzOy91bWJyYWNvL2xpYi9hbmd…:16"

We use Windows ActiveDirectory to login to the UI.

I've run captures using Fiddler but not getting any information back aside from my username and password from the HTTPS session, though I'm new to using Fiddler so might not know how to capture more detail.

(Note: when we restart IIS, the error goes away and logins resume as usual.)

Hi guys. I had the same problem with the Umbraco version 7.7.4 assembly: 1.0.6505.22489. I have tried different ways to solve the problem.

I got a solution when I synchronized my local database with my online database.

The problem was on the table umbracoServer and umbracoUser. I only updated those, and my backoffice started working again.

The other thing is: If you have more than 3 access attempts the Umbraco will block you out.

To fix this you can go to the database, open umbracoUser table and update userNoConsole to 0 for the username that you are trying log in.

I hope helped you guys. Actually I am new in the Umbraco and I will need a lot help. Are we together? :)

Hi,

Even I'm facing the same issue while upgrading from v6.1.6 (Assembly version: 1.0.5021.24867) to v7.12.3.

POST http://mywebsite.local/umbraco/backoffice/UmbracoApi/Authentication/PostLogin 500 (Internal Server Error)

I've checked umbracoServer table and that's empty. Is this correct?

I can see the user that I'm trying to login in umbracoUser table and userDisabled and userNoConsole column is set to 0

Appreciate your response.

Thanks, Pramod

I am also getting same error 500

when i check on console this (umbraco/backoffice/UmbracoApi/Authentication/PostLogin) return 500 error.

Received an error from the server Login failed for user sriaz Could not resolve an instance of Umbraco.Core.Security.BackOfficeSignInManager from the Microsoft.Owin.IOwinContext

EXCEPTION DETAILS: System.NullReferenceException: Could not resolve an instance of Umbraco.Core.Security.BackOfficeSignInManager from the Microsoft.Owin.IOwinContext

Any idea how i will resolve this error

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