Canon EOS 1000F in-built flash unit

Flash not working - autofocus sensor (red light) ok but no flash when taking a picture, when lifting in-built unit up i can here a whinning noise as if it is getting ready but nothing - so I have bought a new flash unit for 1000f (Miranda CAF 28 Flashgun) thinking that the in-built unit faulty but this does not work either (red light) autofocus sensor on new flash unit working but will not flash when taking a picture, also the "Auto Flash" light does not illuminate, the "Test " button works ok.

Same problem with a Canon Ixus 750 (Powershot UK equivalent) . Red light comes on but will not flash