I was doing some quests with the Boomers when I noticed my companion, Ed-E, had disappeared. He wasn't following me anymore, so I backtracked a little, but couldn't find him. Searched the entire Boomer base, which is where I last him him at. So then, I went to Primm to see if he had returned there, but he wasn't there. I went to my hotel room, and still, he wasn't there. I never told him to wait anywhere either. I still get his perk, and the random AI still say things like, "I've never seen an Eyebot like that." Is there anyway to fix this? Cause I saved over my save before I noticed he went missing. Only reason I truly care is cause I can't acquire Rex now, so I can't get the achievement for having all the companions.

im having the EXACT same issue! the last time i saw him was during the run to the gates while dodgeing all the artillery and now hes GONE yet he is supposedly still there!.... OMG hes become a ROBO-GHOST!!!

I too am having the same issue...I made it all the way to Jacobstown and when I went to dismiss Ed-E and take Rex along Ed-E was gone but Rex still thinks he is with me.