diff -r 5af6c74cd793 -r af6ec97d9189 userlibandfileserver/fileserver/sfile/sf_thread.cpp
--- a/userlibandfileserver/fileserver/sfile/sf_thread.cpp	Wed Jun 23 11:59:44 2010 +0100
+++ b/userlibandfileserver/fileserver/sfile/sf_thread.cpp	Wed Jun 23 12:52:28 2010 +0100
@@ -834,10 +834,9 @@
 //
 	{
 	__ASSERT_ALWAYS(FsThreadManager::IsDriveThread(iDriveNumber,EFalse),Fault(EDriveThreadNotifyUser1));
-	// NB For read-ahead or a flush-dirty write request generated by the file cache, the session will be NULL: 
+	// NB For read-ahead or a flush-dirty write request generated by the file cache, the request or the session may be NULL: 
 	// in this case assume that notify user is set (as it's the safest option)
-	CSessionFs* session = iRequest->Session();
-	return session ?  session->GetNotifyUser() : ETrue;
+	return iRequest && iRequest->Session() ?  iRequest->Session()->GetNotifyUser() : ETrue;
 	}
 
 void CDriveThread::StartFinalisationTimer()