How to abandon Levequests

[Enkidoh]

The only time that there is a class restriction on levequests is if you undertake one as a specific class, and you then change classes before turning it in for the reward, you can't complete it until you've switched back to the class you undertook the leve as. So it's likely you've already done that quest as a mage class but haven't yet turned it in and are trying to get the exp on another class like MRD, hence the error stating that you need to be a Discipline of Magic to do so.

[Communion]

Just click on the levequest in question in the list on the right hand side of the screen - it should open up your Journal on the page for that quest. Then simply scroll the page down and click on the 'Abandon' button at the bottom of the page, and click 'yes' when it asks you if you want to abandon it. Simple really.

Incorrect. If you've tried and for any reason were not able to finish the levequest, it is IMPOSSIBLE to abandon. There is no button for it.