I can’t find where to activate the medals (if you even can). There are no medals displayed in the multiplayer or campaign.
Why is this so, is there anything that I can do to fix it or is there and option I’m missing?
Medals should appear automatically when you kill enemies in specific way (multikills, headshots etc). However, from what I’ve played so far, only HCEA campaign gives you medals but not H2A.
So far I’ve done H2A and part of H3 campaigns and no medals showed up in either game, though I keep getting achievements about them.
I can confirm problems with medals. Was playing campaign of Halo 3 in co-op. did a few levels and after one the end of one level, medals were not displayed during the next. Leaving to the start-screen and restarting the level fixed the issue.