The IMSProvider::CompareStoreIDs method compares two message store entry identifiers to determine if they refer to the same store object.
HRESULT CompareStoreIDs(
ULONG cbEntryID1,
LPENTRYID lpEntryID1,
ULONG cbEntryID2,
LPENTRYID lpEntryID2,
ULONG ulFlags,
ULONG FAR * lpulResult
);
MAPI calls the IMSProvider::CompareStoreIDs method while processing a call to the IMAPISession::OpenMsgStore method. CompareStoreIDs is called at this point to determine which profile section, if any, is associated with the message store being opened. A CompareStoreIDs call can be made when no message stores are open for a particular store provider. In addition, MAPI also calls CompareStoreIDs while processing a store provider call to the IMAPISupport::OpenProfileSection method.
The entry identifiers compared by CompareStoreIDs are both for the current store provider's dynamic-link library (DLL) and are both unwrapped store entry identifiers. For more information on wrapping store entry identifiers, see IMAPISupport::WrapStoreEntryID.
Comparing entry identifiers is useful because an object can have more than one valid entry identifier; such a situation can occur, for example, after a new version of a message store provider is installed.
IMAPISession::OpenMsgStore, IMAPISupport::OpenProfileSection, IMAPISupport::WrapStoreEntryID