When using a Umbraco 6.2.5 site and Courier 2.7.8.2. We get the following error on the source server:

error:System.Web.Services.Protocols.SoapException: Server was unable to process request. ---> Could not find the default database provider, please ensure you have all the required DLL's in /bin, and that courier loaded successfully. To debug, turn on debugmode in /config/courier.confg, and examine the /app_data/courier/logs error log files at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall) at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) at Umbraco.Courier.RepositoryProviders.CourierWebserviceRepositoryProvider.OpenSession(String sessionKey) at Umbraco.Courier.Core.Packaging.RevisionPackaging.Package() at Umbraco.Courier.Core.TaskManager.manageTask(IRevisionTask value) 16-9-2015 17:47:57

On the target server the error in the Log appears:

ERROR Umbraco.Core.PluginManager - [Thread 20] Error creating type Umbraco.Courier.Cachehandler.V4.CacheHandler System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> Umbraco.Courier.Core.ProviderException: No provider

We're pretty much stuck here, nothing to be found on the internet about this issue.

The Umbraco installs are both the same. Any help would be appreciated...