I've just lost my companion Veronica, she's nowhere to be found. I did not tell her to stop following me, she just dissapeared at some point.
I've looked in front of the Lucky 38 and at the trading post where I first met her, but she wasn't there.
Is there any way to find a missing companion that is better than searching manually everywhere?
Fallout Wikia has some tips on recovering lost companions who do not appear in either their original location or the Lucky 38. I have not had this problem myself so cannot test.
Update: I can confirm the Vault 22 method worked for me; successfully recovered Rex (on PC).
Here the given trick is to go to Vault 22 and use the central elevator (requires repair skill level 50).
Choose to go to Level 5 - Pest Control.
The missing Companion(s) may be waiting there at the exit of the elevator, you may need to talk to them and ask them to follow you (ie, they may be stuck in wait mode).
This involves using the console commands, I highly recommend saving before messing with the console, and as per Xantec's comment you should be aware this will disable Steam achievements for that play session (ie, you need to fix the game then save and restart).
Here <red_id> is an internal number for the companion - for Veronica this seems to be 000e32a9 - you can get the ID's of others from the Wikia site as well.
This will move the companion to your location:
prid <ref_id>
moveto player
This will move you to the companions current location:
player.moveto <ref_id>
If these don't work the recommendation is to kill and resurrent the companion. First use these two:
prid <ref_id>
OpenTeammateContainer 1
This should give you their inventory windows - empty it into your own.
Then do the following, and hopefully the companion should be back:
moveto player
resurrect 1
disable
enable
I wanted to post a comment, but I'm not able to yet. I hope someone will find this post helpful. I would like to add that, as far as finding lost companions in Vault 22 is concerned, going there is not a solution in every situation. I lost Veronica while diving in Lake Mead - I managed to get ashore and teleported to another location, and she stayed in the water. I thought she would appear in the new location, but she didn't. Going to Vault 22 didn't help - she appeared by the elevator, but she would not follow me outside, and while talking to her there, she would move her hands as though swimming. I had to get back and try to find her, but it was a futile attempt, as I couldn't find her anywhere. I guess loading a previous savegame is the only solution for those who lost their companions under water.
Another Option could be to look for an secure Place (e.g. Lucky 38) and rest there for several hours.
In most cases the Companion returns to you after 48 hours of rest.
At least on PC, you can use the Companion Dismissal Terminal to order all companions to return to wherever their home is, and then go pick them back up at your convenience.
It might be possible companions randomly put themselves into " wait-mode " trace back on all the places you have been and check the local map... If theyre in the area... Their names will show on the map. To check if veronica went into a wait mode, try recruiting another human companion... If they refuse then veronica is waiting somewhere
If you've fought in Thorn, the underground arena outside of Westside South, your companions stay next to Red Lucy in wait until you tell them to follow again. Tried the Vault 22 trick and noticed while I was there that I had to get the mantis eggs for Red Lucy and when I went back to get the caps for them my companions where right there.
On the mini-map there is usually a little arrow with the companion's name on it which you can use to locate your companion.
