I have a 968w with the most recent drivers that I know of.  Pretty much today I needed to simply print on an envelope and it wouldn't do it.  Very frustrating.  All the other functions are working.  It will take the envelope and it sounds as though its printing but nothing is seen on the envelope, either side.  Have tried different configs of the envelope.  Went through TS with the loaded helpware, and selected everything I should have and still nothing.  Its supposed to print in landscape mode for envelopes.  I didn't think it was, so I tried to just print a regular page in landscape and it wouldn't.  Am I missing something?