I have a BOSCH Logixx 8, and solved it as follows:
1. I tried a pliers to force the filter open, bad idea, broke a little piece of the handle.
2. I tried tilting the whole machine and banging as other said, no luck.
3. I removed the back panel, lots of screws. Good access and can see the pump, but difficult to reach.
What worked for me:
4. I removed the bottom front panel, very easy, one screw and the rests are clips.
5. I unscrewed the pump (4 screws, careful with the little wires connecting to the pump) and with a large pliers (small won't do) removed the clip holding the big black hose thus freeing it. Sadly lots of water came out, even though I had drained the machine earlier. It seems all this moving and tilting got more water there, should have drained through the little pipe again.
6. Inside the black hose and the pump I found lots of bra paddings and other strange items! Managed to remove them and then was able easily to open the filter!
Done. Now I know, next time it will be a 5 min job, without having to disconnect and remove the machine!
ITexpert77, May 2016