Applying Davo's Recommended Settings fails with an error

[ItsRetroPup]

[Settings] Failed to apply community guide: Error: Lidarr API error: 500 - Sequence contains no elements

[lklynet]

Thanks for the report.

The error you’re seeing appears to be a Lidarr-side exception that Aurral is surfacing. In practice, this usually happens when Lidarr’s database is in a partially initialized state (missing default profiles) or when running a build that doesn’t fully support the payloads used here.

Workarounds that should resolve it:

• Make sure Lidarr has completed its initial setup and has at least one quality profile and one metadata profile in the UI.
• Upgrade Lidarr to the latest v2 build (custom formats + metadata profile APIs are assumed by this flow).
• If you can’t upgrade, apply the community guide manually in Lidarr as a workaround.

If you can share the Lidarr version and the Lidarr log entry corresponding to the 500, we can pinpoint the exact step that fails and harden the payload to avoid this error.

[ItsRetroPup]

Lidarr:
Version
3.1.0.4875
Package Version
3.1.0.4875-ls20 by linuxserver.io
.NET
Yes (8.0.12)
Docker
Yes
Database
Sqlite 3.50.4
Database Migration
80
AppData Directory
/config
Startup Directory
/app/lidarr/bin
Mode
Console

LOG:

2026/02/20 10:55:44	stdout	[Warn] LidarrErrorPipeline: System.InvalidOperationException: Sequence contains no elements 
2026/02/20 10:55:44	stdout	
2026/02/20 10:55:44	stdout	[v3.1.0.4875] System.InvalidOperationException: Sequence contains no elements
2026/02/20 10:55:44	stdout	   at System.Linq.ThrowHelper.ThrowNoElementsException()
2026/02/20 10:55:44	stdout	   at System.Linq.Enumerable.MaxInteger[TSource,TResult](IEnumerable`1 source, Func`2 selector)
2026/02/20 10:55:44	stdout	   at Lidarr.Api.V1.Profiles.Quality.QualityProfileController.<>c.<.ctor>b__2_6(QualityProfileResource profile, CustomContext context) in ./Lidarr.Api.V1/Profiles/Quality/QualityProfileController.cs:line 38
2026/02/20 10:55:44	stdout	   at FluentValidation.Validators.CustomValidator`1.Validate(PropertyValidatorContext context) in C:\Projects\FluentValidation\src\FluentValidation\Validators\CustomValidator.cs:line 40
2026/02/20 10:55:44	stdout	   at FluentValidation.Internal.PropertyRule.Validate(IValidationContext context)+MoveNext() in C:\Projects\FluentValidation\src\FluentValidation\Internal\PropertyRule.cs:line 351
2026/02/20 10:55:44	stdout	   at FluentValidation.AbstractValidator`1.Validate(ValidationContext`1 context) in C:\Projects\FluentValidation\src\FluentValidation\AbstractValidator.cs:line 95
2026/02/20 10:55:44	stdout	   at Lidarr.Http.REST.RestController`1.ValidateResource(TResource resource, Boolean skipValidate, Boolean skipSharedValidate) in ./Lidarr.Http/REST/RestController.cs:line 108
2026/02/20 10:55:44	stdout	   at Lidarr.Http.REST.RestController`1.OnActionExecuting(ActionExecutingContext context) in ./Lidarr.Http/REST/RestController.cs:line 67
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Mvc.Controller.OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Mvc.Filters.ControllerActionFilter.OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()
2026/02/20 10:55:44	stdout	--- End of stack trace from previous location ---
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)
2026/02/20 10:55:44	stdout	   at Lidarr.Http.Middleware.BufferingMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/BufferingMiddleware.cs:line 27
2026/02/20 10:55:44	stdout	   at Lidarr.Http.Middleware.IfModifiedMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/IfModifiedMiddleware.cs:line 40
2026/02/20 10:55:44	stdout	   at Lidarr.Http.Middleware.CacheHeaderMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/CacheHeaderMiddleware.cs:line 32
2026/02/20 10:55:44	stdout	   at Lidarr.Http.Middleware.StartingUpMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/StartingUpMiddleware.cs:line 37
2026/02/20 10:55:44	stdout	   at Lidarr.Http.Middleware.UrlBaseMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/UrlBaseMiddleware.cs:line 28
2026/02/20 10:55:44	stdout	   at Lidarr.Http.Middleware.VersionMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/VersionMiddleware.cs:line 28
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.ResponseCompression.ResponseCompressionMiddleware.InvokeCore(HttpContext context)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
2026/02/20 10:55:44	stdout	   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.<Invoke>g__Awaited|10_0(ExceptionHandlerMiddlewareImpl middleware, HttpContext context, Task task)
2026/02/20 10:55:44	stdout	
2026/02/20 10:55:44	stdout	
2026/02/20 10:55:44	stdout	[Fatal] LidarrErrorPipeline: Request Failed. POST /api/v1/qualityprofile 

[lklynet]

Hello, can you please update to the latest version and let me know if you're still receiving an error?

[ItsRetroPup]

I ended up doing it manually in the end. Although I did notice everything except the custom formats had actually transferred over.

[dfenech0113]

I am getting the same error on 1.17.1 (Lidarr ver 3.1.0.4875)

[mylogon341]

I'm getting this on v1.28.0 and lidarr v3.1.0.4875.
Authentication seems to work as 'Test' succeeds.

Here are some recent logs from aurral. Let me know if you need anything inspecting in lidarr.

Lidarr API error (400): {
  url: 'http://lidarr.server.local:8686/api/v1/customformat',
  method: 'POST',
  status: 400,
  statusText: 'Bad Request',
  responseData: {
    type: 'https://tools.ietf.org/html/rfc7231#section-6.5.1',
    title: 'One or more validation errors occurred.',
    status: 400,
    traceId: '00-58b5400eedff2010fffc459eeb986b15-26d2b9fac1316b31-00',
    errors: { '$.specifications[0].fields': [Array] }
  },
  responseHeaders: Object [AxiosHeaders] {
    'content-type': 'application/problem+json; charset=utf-8',
    date: 'Fri, 06 Mar 2026 17:56:40 GMT',
    server: 'Kestrel',
    'cache-control': 'no-cache, no-store',
    expires: '-1',
    pragma: 'no-cache',
    'transfer-encoding': 'chunked',
    'x-application-version': '2.13.3.4711'
  }
}
Lidarr API error (400): {
  url: 'http://lidarr.server.local:8686/api/v1/customformat',
  method: 'POST',
  status: 400,
  statusText: 'Bad Request',
  responseData: {
    type: 'https://tools.ietf.org/html/rfc7231#section-6.5.1',
    title: 'One or more validation errors occurred.',
    status: 400,
    traceId: '00-8eacf925f77428086f468cf5126aa159-5580967a4886b11b-00',
    errors: { '$.specifications[0].fields': [Array] }
  },
  responseHeaders: Object [AxiosHeaders] {
    'content-type': 'application/problem+json; charset=utf-8',
    date: 'Fri, 06 Mar 2026 17:56:40 GMT',
    server: 'Kestrel',
    'cache-control': 'no-cache, no-store',
    expires: '-1',
    pragma: 'no-cache',
    'transfer-encoding': 'chunked',
    'x-application-version': '2.13.3.4711'
  }
}
Lidarr API error (500): {
  url: 'http://lidarr.server.local:8686/api/v1/qualityprofile',
  method: 'POST',
  status: 500,
  statusText: 'Internal Server Error',
  responseData: {
    message: 'Sequence contains no elements',
    description: 'System.InvalidOperationException: Sequence contains no elements\n' +
      '   at System.Linq.ThrowHelper.ThrowNoElementsException()\n' +
      '   at System.Linq.Enumerable.Max[TSource](IEnumerable`1 source, Func`2 selector)\n' +
      '   at Lidarr.Api.V1.Profiles.Quality.QualityProfileController.<>c.<.ctor>b__2_6(QualityProfileResource profile, CustomContext context) in ./Lidarr.Api.V1/Profiles/Quality/QualityProfileController.cs:line 38\n' +
      '   at FluentValidation.Validators.CustomValidator`1.Validate(PropertyValidatorContext context) in C:\\Projects\\FluentValidation\\src\\FluentValidation\\Validators\\CustomValidator.cs:line 41\n' +
      '   at FluentValidation.Internal.PropertyRule.InvokePropertyValidator(IValidationContext context, IPropertyValidator validator, String propertyName) in C:\\Projects\\FluentValidation\\src\\FluentValidation\\Internal\\PropertyRule.cs:line 519\n' +
      '   at FluentValidation.Internal.PropertyRule.Validate(IValidationContext context)+MoveNext() in C:\\Projects\\FluentValidation\\src\\FluentValidation\\Internal\\PropertyRule.cs:line 351\n' +
      '   at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext()\n' +
      '   at FluentValidation.AbstractValidator`1.Validate(ValidationContext`1 context) in C:\\Projects\\FluentValidation\\src\\FluentValidation\\AbstractValidator.cs:line 95\n' +
      '   at Lidarr.Http.REST.RestController`1.ValidateResource(TResource resource, Boolean skipValidate, Boolean skipSharedValidate) in ./Lidarr.Http/REST/RestController.cs:line 122\n' +
      '   at Lidarr.Http.REST.RestController`1.OnActionExecuting(ActionExecutingContext context) in ./Lidarr.Http/REST/RestController.cs:line 67\n' +
      '   at Microsoft.AspNetCore.Mvc.Controller.OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()\n' +
      '--- End of stack trace from previous location ---\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)\n' +
    'x-application-version': '3.1.0.4875'
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)\n' +
  }
}
      '   at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)\n' +
      '   at Lidarr.Http.Middleware.BufferingMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/BufferingMiddleware.cs:line 28\n' +
Lidarr API error (400): {
  url: 'http://lidarr.server.local:8686/api/v1/customformat',
  method: 'POST',
  status: 400,
  statusText: 'Bad Request',
      '   at Lidarr.Http.Middleware.IfModifiedMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/IfModifiedMiddleware.cs:line 41\n' +
  responseData: {
      '   at Lidarr.Http.Middleware.CacheHeaderMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/CacheHeaderMiddleware.cs:line 33\n' +
    type: 'https://tools.ietf.org/html/rfc9110#section-15.5.1',
      '   at Lidarr.Http.Middleware.StartingUpMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/StartingUpMiddleware.cs:line 38\n' +
    title: 'One or more validation errors occurred.',
    status: 400,
    errors: { '$.specifications[0].fields': [Array] },
      '   at Lidarr.Http.Middleware.UrlBaseMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/UrlBaseMiddleware.cs:line 29\n' +
    traceId: '00-3a9fbcce0f76be32ae9028af9b67e452-ee75ce427b5f90df-00'
      '   at Lidarr.Http.Middleware.VersionMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/VersionMiddleware.cs:line 29\n' +
  },
      '   at Microsoft.AspNetCore.ResponseCompression.ResponseCompressionMiddleware.InvokeCore(HttpContext context)\n' +
  responseHeaders: Object [AxiosHeaders] {
      '   at Microsoft.AspNetCore.Authorization.Policy.AuthorizationMiddlewareResultHandler.HandleAsync(RequestDelegate next, HttpContext context, AuthorizationPolicy policy, PolicyAuthorizationResult authorizeResult)\n' +
    'content-type': 'application/problem+json; charset=utf-8',
      '   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)\n' +
    date: 'Fri, 06 Mar 2026 18:06:28 GMT',
      '   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)\n' +
    server: 'Kestrel',
      '   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.<Invoke>g__Awaited|6_0(ExceptionHandlerMiddleware middleware, HttpContext context, Task task)'
    'cache-control': 'no-cache, no-store',
  },
    expires: '-1',
  responseHeaders: Object [AxiosHeaders] {
    pragma: 'no-cache',
    'content-type': 'application/json',
    'transfer-encoding': 'chunked',
    date: 'Fri, 06 Mar 2026 17:56:42 GMT',
    'x-application-version': '3.1.0.4875'
    server: 'Kestrel',
  }
}
Lidarr API error (400): {
    'cache-control': 'no-cache,no-store',
    expires: '-1',
  url: 'http://lidarr.server.local:8686/api/v1/customformat',
    pragma: 'no-cache',
  method: 'POST',
  status: 400,
    'transfer-encoding': 'chunked'
  }
  statusText: 'Bad Request',
}
  responseData: {
[Settings] Failed to apply community guide: Error: Lidarr API error: 500 - Sequence contains no elements
    at LidarrClient.request (file:///app/backend/services/lidarrClient.js:397:17)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async file:///app/backend/routes/settings.js:763:25
    type: 'https://tools.ietf.org/html/rfc9110#section-15.5.1',
    title: 'One or more validation errors occurred.',
    status: 400,
    errors: { '$.specifications[0].fields': [Array] },
    traceId: '00-f884d798e69a5a816dedcfac6bbbbb8d-755f5c543f03c67d-00'
  },
  responseHeaders: Object [AxiosHeaders] {
    'content-type': 'application/problem+json; charset=utf-8',
    date: 'Fri, 06 Mar 2026 18:06:28 GMT',
    server: 'Kestrel',
    'cache-control': 'no-cache, no-store',
    expires: '-1',
    pragma: 'no-cache',
    'transfer-encoding': 'chunked',
    'x-application-version': '3.1.0.4875'
  }
}
Lidarr API error (500): {
  url: 'http://lidarr.server.local:8686/api/v1/qualityprofile',
  method: 'POST',
  status: 500,
  statusText: 'Internal Server Error',
  responseData: {
    message: 'Sequence contains no elements',
    description: 'System.InvalidOperationException: Sequence contains no elements\n' +
      '   at System.Linq.ThrowHelper.ThrowNoElementsException()\n' +
      '   at System.Linq.Enumerable.MaxInteger[TSource,TResult](IEnumerable`1 source, Func`2 selector)\n' +
      '   at Lidarr.Api.V1.Profiles.Quality.QualityProfileController.<>c.<.ctor>b__2_6(QualityProfileResource profile, CustomContext context) in ./Lidarr.Api.V1/Profiles/Quality/QualityProfileController.cs:line 38\n' +
      '   at FluentValidation.Validators.CustomValidator`1.Validate(PropertyValidatorContext context) in C:\\Projects\\FluentValidation\\src\\FluentValidation\\Validators\\CustomValidator.cs:line 41\n' +
      '   at FluentValidation.Internal.PropertyRule.Validate(IValidationContext context)+MoveNext() in C:\\Projects\\FluentValidation\\src\\FluentValidation\\Internal\\PropertyRule.cs:line 351\n' +
      '   at System.Linq.Enumerable.WhereEnumerableIterator`1.MoveNext()\n' +
      '   at FluentValidation.AbstractValidator`1.Validate(ValidationContext`1 context) in C:\\Projects\\FluentValidation\\src\\FluentValidation\\AbstractValidator.cs:line 95\n' +
      '   at FluentValidation.AbstractValidator`1.Validate(T instance) in C:\\Projects\\FluentValidation\\src\\FluentValidation\\AbstractValidator.cs:line 62\n' +
      '   at Lidarr.Http.REST.RestController`1.ValidateResource(TResource resource, Boolean skipValidate, Boolean skipSharedValidate) in ./Lidarr.Http/REST/RestController.cs:line 108\n' +
      '   at Lidarr.Http.REST.RestController`1.OnActionExecuting(ActionExecutingContext context) in ./Lidarr.Http/REST/RestController.cs:line 67\n' +
      '   at Microsoft.AspNetCore.Mvc.Controller.OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)\n' +
      '   at Microsoft.AspNetCore.Mvc.Filters.ControllerActionFilter.OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next)\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()\n' +
      '--- End of stack trace from previous location ---\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeFilterPipelineAsync>g__Awaited|20_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)\n' +
      '   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Awaited|17_0(ResourceInvoker invoker, Task task, IDisposable scope)\n' +
      '   at Lidarr.Http.Middleware.BufferingMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/BufferingMiddleware.cs:line 27\n' +
      '   at Lidarr.Http.Middleware.IfModifiedMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/IfModifiedMiddleware.cs:line 40\n' +
      '   at Lidarr.Http.Middleware.CacheHeaderMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/CacheHeaderMiddleware.cs:line 32\n' +
      '   at Lidarr.Http.Middleware.StartingUpMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/StartingUpMiddleware.cs:line 37\n' +
      '   at Lidarr.Http.Middleware.UrlBaseMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/UrlBaseMiddleware.cs:line 28\n' +
      '   at Lidarr.Http.Middleware.VersionMiddleware.InvokeAsync(HttpContext context) in ./Lidarr.Http/Middleware/VersionMiddleware.cs:line 28\n' +
      '   at Microsoft.AspNetCore.ResponseCompression.ResponseCompressionMiddleware.InvokeCore(HttpContext context)\n' +
      '   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)\n' +
      '   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)\n' +
      '   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddlewareImpl.<Invoke>g__Awaited|10_0(ExceptionHandlerMiddlewareImpl middleware, HttpContext context, Task task)'
  },
  responseHeaders: Object [AxiosHeaders] {
    'content-type': 'application/json',
    date: 'Fri, 06 Mar 2026 18:06:29 GMT',
    server: 'Kestrel',
    'cache-control': 'no-cache,no-store',
    expires: '-1',
    pragma: 'no-cache',
    'transfer-encoding': 'chunked'
  }
}
[Settings] Failed to apply community guide: Error: Lidarr API error: 500 - Sequence contains no elements
    at LidarrClient.request (file:///app/backend/services/lidarrClient.js:397:17)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async file:///app/backend/routes/settings.js:763:25