I am registering for storewide events with the Exchange server 2000 and windows 2000. I am using the ATL COM in vc++ and registering with Exchange server as a COM+ application. When i am registering for only OnsyncSave and OnSyncDelete and use MAPI for finding out the details about the Mailbox data then I am able to Open the Private Store using HrOpenExchangePrivateStore But when i register for the system events(OnmDBShutDown and OnMDBStartUp) first i was not able to initialize MAPI also. Then when i used the CoInitialize i could initialize MAPI but the HrOpenExchangePrivateStore is failing with the Error code 80004005 (-2147467259)which is E_FAIL (unspecified error). Does any of you know why is that and what i should do to solve that? I initialized MAPI like this, CoInitializeEx (NULL,COINIT_MULTITHREADED); MAPIINIT_0 mapiInit; mapiInit.ulVersion = 0; mapiInit.ulFlags = MAPI_MULTITHREAD_NOTIFICATIONS | MAPI_NO_COINIT; MAPIInitialize (&mapiInit); Thanks a lotz in Advance, Melbin