I recently flew with Cathay Pacific in economy and now Qantas is rejecting my frequent flyer point claim. Is there a way to check which fare class I bought based on my e-ticket?
Assuming you accrued their 'Asia Miles' for the flight, you can log in and have a look at that. When you click the 'compare fare types' link, 'mileage accrual' will be shown in Fare Types section, indicating the specific fare class code.
Failing that, the code may be on your ticket.
If it's Fare classes W, R and T on Qantas Airways earn 110% mileage/sector accrual.
If it's Y then you should be eligible for 100% Club miles and Club sectors accrual.
If it's B/H/K/L/M/V then you should be eligible for 50% Club miles and Club sectors accrual.
And http://downloads.asiamiles.com/pdf/programme/amonline_membersguide_en.pdf is a handy link for the full manual for their Asia Miles programme (if you're using that).
Otherwise a quick call to your travel agent / the airline directly and you will be able to get the fare class and an explanation of what that means as well.