I tried this once and it worked......use a vacuum cleaner nozzle on a very light suck setting to suck back the membrane if it becomes deformed or flattened in....but only try it if you are prepared for the worst.
That said sometimes you have to just replace the whole cartridge or buy a new mic as repairs can cost way more than the mic is worth.

PS I just spotted this on Ebay.....a guy is selling a starcloth plus a free beta 87c mic for £50......BARGAIN....even if you throw away the starcloth. Maybe he will ship to Denmark.
http://www.ebay.co.uk/itm/120-LED-W...ngLEDsStrobes_RL&hash=item3a6ac287f7