Using FsrmQuotaManager with a WCF service

I'm using a WCF service that is running on an IIS 7.5 (W2k8 R2). I use this service for getting quota information about the space of a specified web site on the same IIS.

So I do have the WCF service acting as server and a local web app acting as client. The client now asks the server for the quota of a web site folder. To do so the server should use the FsrmQuotaManager. But when the service is referencing the quota manager I get an 0x80070005 (Access denied). The web service runs in it's own开发者_运维问答 AppPool with the ApplicationPoolIdentity.

I always got DistributedCOM errors (10016) in the event log saying that The machine-default permission settings do not grant Local Activation permission for the COM Server application with CLSID {90DCAB7F-347C-4BFC-B543-540326305FBE} and APPID {FA3FC5CF-0304-4CAC-99F0-032AC2B15D1E} to the user MYDOMAIN\someUsername SID (S-1-5-21-1477432904-898564541-3754644009-3102) from address LocalHost (Using LRPC). This security permission can be modified using the Component Services administrative tool. So I already managed to add permission for this user (or better the group that user is in) in the ComponentServices as I often read when searching the Internet. Now I don't get that error in the event viewer anymore but when I'm referencing the FsrmQuotaManager in the services code I'm still getting the exception.

Does anyone have a clue about that? I'm really stuck at this for quite some days and I'm running out of ideas. Using the Process Monitordoesn't help.

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We finally solved it.
We had to impersonate around the creation of the FsrmQuotaManager object with a local administrator account. Using this we could also remove the the permission previously added in the ComponentServices.