I have a hosted instance of umbraco 4.5.2 at Pipten (UK provider) and I am getting error messages relating to access the umbraco.config file. I have been in touch with the support (who are very helpful) and they have said:

here are no other permissions that can be changed. The service runs as identity impersonate and has full permissions to all your files. 

There are several instances of the same error in the trace and I can consistently reproduce it when publishing a blog entry (BlogForUmbraco 2.0.26). 

Event Type: Error

Event Source: ASP.NET 4.0.30319.0

Event Category: None

Event ID: 1325

Date: 14/06/2011

Time: 15:43:51

User: N/A

Computer: DWIN20

Description:

An unhandled exception occurred and the process was terminated.

 

Application ID: /LM/W3SVC/119/ROOT

 

Process ID: 8968

 

Exception: System.UnauthorizedAccessException

 

Message: Access to the path 'xxxxxx\App_Data\umbraco.config' is denied.

 

StackTrace:    at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)

   at System.IO.File.SetAttributes(String path, FileAttributes fileAttributes)

   at umbraco.content.DeleteXmlCache()

   at umbraco.content.PersistXmlToFile(XmlDocument xmlDoc)

   at umbraco.content.<RefreshContentFromDatabaseAsync>b__0(Object )

   at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context(Object state)

   at System.Threading.ExecutionContext.runTryCode(Object userData)

   at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)

   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)

   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)

   at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()

   at System.Threading.ThreadPoolWorkQueue.Dispatch()

   at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()

 

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