diff --git a/dlls/combase/combase.spec b/dlls/combase/combase.spec
index 0437714edcc..7343da6a0ef 100644
--- a/dlls/combase/combase.spec
+++ b/dlls/combase/combase.spec
@@ -85,7 +85,7 @@
 @ stdcall CoCreateInstanceFromApp(ptr ptr long ptr long ptr)
 @ stub CoCreateObjectInContext
 @ stub CoDeactivateObject
-@ stub CoDecodeProxy
+@ stdcall CoDecodeProxy(long int64 ptr)
 @ stdcall CoDecrementMTAUsage(ptr)
 @ stdcall CoDisableCallCancellation(ptr)
 @ stub CoDisconnectContext
diff --git a/dlls/combase/rpc.c b/dlls/combase/rpc.c
index 55450ad7f14..7337498e9fa 100644
--- a/dlls/combase/rpc.c
+++ b/dlls/combase/rpc.c
@@ -2109,3 +2109,12 @@ BOOL WINAPI DllDebugObjectRPCHook(BOOL trace, /* ORPC_INIT_ARGS * */ void *args)
 
     return TRUE;
 }
+
+/******************************************************************************
+ *            CoDecodeProxy    (combase.@)
+ */
+HRESULT WINAPI CoDecodeProxy(DWORD client_pid, UINT64 proxy_addr, ServerInformation *server_info)
+{
+    FIXME("%x %s %p\n", client_pid, wine_dbgstr_longlong(proxy_addr), server_info);
+    return E_NOTIMPL;
+}