This interface is implemented by EXPLORER to support the notification area of the taskbar. The IID is:

IID_ITrayNotify {FB852B2C-6BAD-4605-9551-F15F87830935}

The ITrayNotify methods are (as ordered in the virtual function table after the IUnknown methods):

Offset Method
0x0C RegisterCallback
0x10 SetPreference
0x14 EnableAutoTray

with prototypes:

HRESULT RegisterCallback (INotificationCB *);
HRESULT SetPreference (NOTIFYITEM const *);
HRESULT EnableAutoTray (BOOL);

in which INotificationCB is an undocumented interface and NOTIFYITEM is an undocumented structure.


The only known implementation of the ITrayNotify interface is by EXPLORER for an internal class, named CTrayNotify, which supports the notification area on the Windows taskbar. One instance is created internally. This same instance is also exposed as a creatable COM class with the following CLSID:

CLSID_TrayNotify {25DEAD04-1EAC-4911-9E3A-AD0A4AB560FD}


The ITrayNotify interface is implemented by EXPLORER version 6.00 and higher.

Though this interface dates from 2001, it was still not documented by Microsoft as late as the January 2007 edition of the Windows Vista Software Development Kit (SDK).