So when i went to talk to the people at the college of winterhold, i retty much go the same quest as if i did almost ALL of the main story line, and they even told me to go to the guy who you get the oghma infinium from, and then in the quest description it says i should go to said person to get the elderscroll for parthunax, seriously?! I havent even STARTED the MQ, is this going to effect my main story?

it will only slightly affect the main story nothing plot breaking or anything just takes the chunk out where you would need to go find the scroll.

It didn't say anything abotu Paarthurnax in mine ... weird.

What I reckon is meant to happen is that when it comes to that particular part of the MQ, you've already got the Elder Scroll, and can bypass it. I dunno about yours though.

Please use the http://www.gamesas.com/forum/196-dawnguard-cheats-hints-and-spoilers/