Having troubles printing envelopes. Have Windows XP Home Edition, a Lexmark X75 printer and using WordPerfect 10, documents print fine but when I try to print an envelope nothing prints. I've tried using another program to print an envelope and the same thing happens, document comes out blank. Also, have changed ink cartridges and sometimes print will be black on screen but document will be blue or red on paper. This problem is driving me nuts. Could my printer be bad? Do I need to clean something? Is there a setting that needs to be changed on my pc to print envelopes? I just printed a bunch last week and they came out fine, now it's not working. Help!