I recently did the quest to retrieve Potema's remains. I rode Shadowmere to Solitude, and went on the quest which takes you underground from Solitude up into the mountains behind it, and when I came out after completing the dungeon, Shadowmere was gone, but not simply gone, REPLACED by another generic and worthless horse. I'm furious. I've done everything that I know to do. My most recent save is outside of the dungeon, and the one before that is 20 levels (I'm level 39) and 20 hours back.

Is there a place where Shadowmere respawns when (s)he gets lost? I keep reading that she respawns after like 15-20 days where she is KILLED, but what about if she just disappears?!?! Not only that, but is REPLACED by another horse. I have never even ridden on another horse, and yet this crappy generic horse has literally replaced Shadowmere and is "mine" according to the game. I call bull, because I've never ridden another horse BECAUSE of the fact that I could lose Shadowmere.

This is my first big glitch, and it's big enough to stop me from playing for a very long time. I've had Shadowmere for almost the entire game. There should be a freaking "home" location that she goes to when the game screws up and you lose her.

I'm beyond furious.

I think, when she dies at least, she respawns outside the Dark Brotherhood sanctuary where she first spawned after 20 game days.

Are you sure you just didn't happen to find the wrong horse? I've run across at least one random horse that I could ride without it being theft. Go search around the dungeon exterior to be 100% sure.

He used to be a horse, until he took an arrow to the knee.

Same thing has happened to my sister. She says Shadowmere just started flying sideways off into Skyrim. Never saw the horse again sadly.