skype is a 32 bit program
there are things you need to tell us 64 bit system 32 bit system. and after you have searched a well documented reason for this. most likely the skype forum you have a 64 bit system.
If not oh well same thing for the 32 bit just a different place to look in the system
this is a very simple problem well documented for skype and Ubuntu.
sudo apt-get install lib32v4l-0
then for gspca cams old ones in a console type LD_PRELOAD=/usr/lib32/libv4l/v4l1compat.so skype for new cams typeLD_PRELOAD=/usr/lib32/libv4l/v4l2compat.so skype More info here
you will want to edit your menus so all you have to do is click on skype this is a skype problem. we cant fix it it is not an open source program.