Skip to main content

TFS Build error - System.InvalidCastException: Unable to cast COM object of type 'System.__ComObject' to interface type 'Microsoft.Web.Administration.Interop.IAppHostWritableAdminManager'.

After replacing one of our build servers, we got the following error when trying to execute a custom XAML build Workflow activity:

System.InvalidCastException: Unable to cast COM object of type 'System.__ComObject' to interface type 'Microsoft.Web.Administration.Interop.IAppHostWritableAdminManager'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{FA7660F6-7B3F-4237-A8BF-ED0AD0DCBBD9}' failed due to the following error: Interface not registered (Exception from HRESULT: 0x80040155).

at Microsoft.Web.Administration.ConfigurationManager.CreateAdminManager[TClass,TInterface](WebConfigurationMap webConfigMap, Boolean isAdminConfig)

at Microsoft.Web.Administration.ConfigurationManager.CreateConfiguration(WebConfigurationMap configMap, String configPathToEdit, Boolean isAdminConfig)

at Microsoft.Web.Administration.ConfigurationManager.GetConfiguration(String rawConfigurationPath, String cacheKey, Boolean isAdminConfig)

at Microsoft.Web.Administration.ServerManager.get_ApplicationPoolsSection()

at Microsoft.Web.Administration.ServerManager.get_ApplicationPools()

at Microsoft.Web.Administration.ServerManagerExtensions.TryGetAppPool(ServerManager serverManager, String appPoolName, ApplicationPool& result)

at Customer.TeamFoundation.Build.Workflow.Activities.ControlAppPool.InnerExecute(CodeActivityContext context)

This activity tries to talk to IIS on our test environment to stop and restart the application pool after installation. The reason why it failed is because this activity requires IIS installed on the build server to allow remote administration.

After installing it, our XAML builds turned all green again…

Popular posts from this blog

.NET 8–Keyed/Named Services

A feature that a lot of IoC container libraries support but that was missing in the default DI container provided by Microsoft is the support for Keyed or Named Services. This feature allows you to register the same type multiple times using different names, allowing you to resolve a specific instance based on the circumstances. Although there is some controversy if supporting this feature is a good idea or not, it certainly can be handy. To support this feature a new interface IKeyedServiceProvider got introduced in .NET 8 providing 2 new methods on our ServiceProvider instance: object? GetKeyedService(Type serviceType, object? serviceKey); object GetRequiredKeyedService(Type serviceType, object? serviceKey); To use it, we need to register our service using one of the new extension methods: Resolving the service can be done either through the FromKeyedServices attribute: or by injecting the IKeyedServiceProvider interface and calling the GetRequiredKeyedServic...

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.

Kubernetes–Limit your environmental impact

Reducing the carbon footprint and CO2 emission of our (cloud) workloads, is a responsibility of all of us. If you are running a Kubernetes cluster, have a look at Kube-Green . kube-green is a simple Kubernetes operator that automatically shuts down (some of) your pods when you don't need them. A single pod produces about 11 Kg CO2eq per year( here the calculation). Reason enough to give it a try! Installing kube-green in your cluster The easiest way to install the operator in your cluster is through kubectl. We first need to install a cert-manager: kubectl apply -f https://github.com/cert-manager/cert-manager/releases/download/v1.14.5/cert-manager.yaml Remark: Wait a minute before you continue as it can take some time before the cert-manager is up & running inside your cluster. Now we can install the kube-green operator: kubectl apply -f https://github.com/kube-green/kube-green/releases/latest/download/kube-green.yaml Now in the namespace where we want t...