Had real good luck with using vacuum cleaner to remove dust/hair/trash inside C-2100 EVF. (Actually got my 1st trash in the EVF trying to clean lens with can of compressed air & realized that procedure this is no no.)
(Also, some people clean their EVF by removing the eye piece via removing the EVF housing hold down screws. This constitutes disassembly of the camera & voids the warranty - 3yrs in my case. Also, probably results in unsightly swedged screw head slots indicating tampering.)
Anyway, procedure is to orient camera vertically with lens pointing to sky then put vacuum cleaner nozzel at full force to EVF eye piece. In addition, clasp fingers to close/minimize gap between EVF & cleaner nozzel to maximize vacuum (try to get as much vacuum as you can - don't be afraid - you wont rip out any camera guts). If you can, exercise the diopter adjuster [back & forth] during the suction procedure as that faciltates opening the "air gap" between EVF lens & housing. Also, tapping the camera with your finger during the procedure facilitates partical losening.
I've done this many times & had no issues or bad effects (ie, dirt only gets less).