I once experienced a weird problem with OLCI for a mixture of NW and CO flights (NW E-ticket). The itinerary was BWI-MSP-EWR on NW and EWR-FLL on CO. I got upgraded on all segments four days before departure. However, on the day before departure, no matter how hard I tried to do OLCI to save NW some penny, nwa.com just refused to let me do it. nwa.com online support could not figure out why; the elite line told me it might be due to the fact I got upgraded on the CO segment. The weird thing was, I could not check in using kiosk, either; plus that the NW agents at both BWI and MSP could not give me boarding pass for EWR-FLL because they told me CO controlled my EWR-FLL. Finally when I arrived at EWR, I asked for the BP again at CO counter. The agent told me it was paper ticket. I then got completely confused and told her what happened. She then called some supervisor, after spending about 10 minutes, she finally solved this problem for me.

I have booked an award trip to Brazil (outbound on NW and DL, return on CO and NW) which has some odd things, too. This ticket was issued by NW as E-ticket; however, when I looked at my itinerary at continental.com, it states that this is a paper ticket. Also, on delta.com, it says one of the segments IAH-EWR booked in G class on CO is first class but both nwa.com and continental.com says it is coach class (the whole trip is booked in coach class). To me, there is some miscommunication between NW, CO and DL which needs to be fixed. I haven't bothered to call NW or CO about this. Does anybody here have some clue?