For newer 2sxc Versions

Look at this Checklist

Cause of the Error

This error occurs if you had a 2sxc version around April 2019 which accidentally created the same content-type a few times. It's rare, but can happen. 

1. Open the DB in SQL Management Studio
2. Open the table dbo.ToSIC_EAV_AttributeSets in edit mode 
3. Edit the SQL, then change the SQL to show all the types - in this case App-Settings: 
   SELECT TOP (200) *
   FROM ToSIC_EAV_AttributeSets
   WHERE (Name = 'App-Settings')
   ORDER BY AppID
4. Now look of the cases where the same AppId has this content-type multiple times and write down all the AttributeSetID
5. Check in the Entities-table if this content-type is in use,
6. Then go back to the AttributeSets and delete the ones that are not in use

Full Error Message (for SEO)

Error: Your-App-Name is currently unavailable. DotNetNuke.Services.Exceptions.ModuleLoadException: too many or to few content types found for the content-type App-Settings - found 3 ---> System.Exception: too many or to few content types found for the content-type App-Settings - found 3 at ToSic.Eav.Repository.Efc.Parts.DbAttributeSet.GetDbAttribSetWithEitherName(String name) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbAttributeSet.cs:line 59 at ToSic.Eav.Repository.Efc.Parts.DbAttributeSet.GetIdWithEitherName(String name) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbAttributeSet.cs:line 67 at ToSic.Eav.Repository.Efc.Parts.DbEntity.SaveEntity(IEntity newEnt, SaveOptions so) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbEntity_save.cs:line 69 at ToSic.Eav.Repository.Efc.Parts.DbEntity.<>c__DisplayClass16_1.<SaveEntity>b__3() in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbEntity_save.cs:line 419 at ToSic.Eav.Repository.Efc.DbDataController.DoAndSave(Action action) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\DbDataController.cs:line 234 at ToSic.Eav.Repository.Efc.Parts.DbEntity.<>c__DisplayClass16_0.<SaveEntity>b__2(IEntity e) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbEntity_save.cs:line 419 at System.Collections.Generic.List`1.ForEach(Action`1 action) at ToSic.Eav.Repository.Efc.Parts.DbEntity.<>c__DisplayClass16_0.<SaveEntity>b__1() in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbEntity_save.cs:line 419 at ToSic.Eav.Repository.Efc.Parts.DbVersioning.QueueDuringAction(Action action) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbVersioning.cs:line 48 at ToSic.Eav.Repository.Efc.Parts.DbEntity.<>c__DisplayClass16_0.<SaveEntity>b__0() in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbEntity_save.cs:line 416 at ToSic.Eav.Repository.Efc.DbDataController.DoInTransaction(Action action) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\DbDataController.cs:line 258 at ToSic.Eav.Repository.Efc.Parts.DbEntity.SaveEntity(List`1 entities, SaveOptions saveOptions) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbEntity_save.cs:line 415 at ToSic.Eav.Repository.Efc.DbDataController.Save(List`1 entities, SaveOptions saveOptions) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\DbDataController.cs:line 294 at ToSic.Eav.Apps.Parts.EntitiesManager.<>c__DisplayClass13_0.<Save>b__1() at ToSic.Eav.Repository.Efc.Parts.DbRelationship.DoWhileQueueingRelationships(Action action) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\Parts\DbRelationship.cs:line 24 at ToSic.Eav.Repository.Efc.DbDataController.DoWhileQueueingRelationships(Action action) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\DbDataController.cs:line 289 at ToSic.Eav.Apps.Parts.EntitiesManager.<>c__DisplayClass13_0.<Save>b__0() at ToSic.Eav.Repository.Efc.DbDataController.DoButSkipAppCachePurge(Action action) in C:\Projects\eav-server\ToSic.Eav.Repository.Efc\DbDataController.cs:line 272 at ToSic.Eav.Apps.Parts.EntitiesManager.Save(List`1 entities, SaveOptions saveOptions) at ToSic.Eav.Apps.Parts.EntitiesManager.Save(IEntity entity, SaveOptions saveOptions) at ToSic.Eav.Apps.AppManager.MetadataEnsureTypeAndSingleEntity(String scope, String setName, String label, Int32 appAssignment, Dictionary`2 values, Boolean inAppType) at ToSic.Eav.Apps.AppManager.EnsureAppIsConfigured(String appName) at ToSic.Eav.Apps.App..ctor(Int32 zoneId, Int32 appId, Boolean allowSideEffects, Func`2 buildConfiguration, ILog parentLog, String logMsg) at ToSic.Eav.Apps.App..ctor(IAppEnvironment env, ITenant tenant, Int32 zoneId, Int32 appId, Boolean allowSideEffects, Func`2 buildConfiguration, ILog parentLog) at ToSic.Eav.Apps.App..ctor(ITenant tenant, Int32 zoneId, Int32 appId, Boolean allowSideEffects, Func`2 buildConfiguration, ILog parentLog) at ToSic.Sxc.Apps.App..ctor(ITenant tenant, Int32 zoneId, Int32 appId, Func`2 buildConfig, Boolean allowSideEffects, ILog parentLog) in C:\Projects\2sxc-dnn742\Website\DesktopModules\ToSIC_SexyContent\ToSic.Sxc\Apps\App.cs:line 79 at ToSic.Sxc.Blocks.BlockFromModule..ctor(IContainer container, ILog parentLog, ITenant tenant, IEnumerable`1 overrideParams) in C:\Projects\2sxc-dnn742\Website\DesktopModules\ToSIC_SexyContent\ToSic.Sxc\Blocks\BlockFromModule.cs:line 72 at ToSic.SexyContent.View.get_CmsBlock() in C:\Projects\2sxc-dnn742\Website\DesktopModules\ToSIC_SexyContent\View.ascx.cs:line 28 at ToSic.SexyContent.View.EnsureCmsBlockAndPortalIsReady() in C:\Projects\2sxc-dnn742\Website\DesktopModules\ToSIC_SexyContent\View.ascx.cs:line 124 at ToSic.SexyContent.View.<Page_Load>b__7_0() in C:\Projects\2sxc-dnn742\Website\DesktopModules\ToSIC_SexyContent\View.ascx.cs:line 63 at ToSic.SexyContent.View.TryCatchAndLogToDnn(Action action, Action`1 timerWrap) in C:\Projects\2sxc-dnn742\Website\DesktopModules\ToSIC_SexyContent\View.ascx.cs:line 154 --- End of inner exception stack trace ---

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