This is my second playthrough of FO3 on my PC.

The first time I was out wandering the wastes (after already meeting and saving them at the hotel) and out of no where comes Donovan shooting at some raiders and I and he engage them in a big firefight.

Unfortunately he gets his ass handed to him and dies.

I loot his stuff, kept his wrench on me, had an extra suit of Ranger combat armor, and went on. Kept returning to the compound to turn in my locations to Reilly without incident.

This time something else happened. Once again (long after saving them on the hotel roof top) I ran into Donovan out in the wastes. Not entirely sure how he died because there were death claws and grenades and raiders and stuff. Suddenly I realized he was laying there dead. Stripped him like last time, went on my way.

However now when I go to the compound they fire at me.

Starting to wonder if I accidentally killed him when I was hurling those grenades at the raiders. Whoops.

I had a similar problem once where I must have accidentally hurt a Brotherhood Outcast or one of their robots. I found a link somewhere where someone gave a programming code to enter in via the control console (the one accessed by pressing ~ ) and some script that reset them to friendly. Sure enough it worked.

Is there anything like that for Reilly's Rangers? Donovan's dead and gone but I'd like to still be able to take locations back to Riley.

Hmm, I was looking here http://fallout.wikia.com/wiki/Fallout_3_console_commands and "setally (0/1 optional) (0/1 optional) - sets a faction as an ally with another specified faction. 0=Ally 1=Friend." might work ... but I don't see a faction ID for Reilly's Rangers.

Sorry, but that's all I've got and I'm not certain it'd work even with a faction ID, never tried it.

I think I did that with the Outcasts to get them to stop shooting at me.

Hmmmm.