Hidden Valley computer virus

The Hidden Valley computer virus refers to an unmarked quest in Fallout: New Vegas.

Detailed walkthrough
The Brotherhood of Steel found a holotape while searching the wastes for technology. When it was put onto the system, it infected their database terminals with a virus. The virus was originally put on a holotape by "some pre-War jackass with nothing better to do", as said by the annoyed Scribe Ibsen. The computer virus infected a few computers in the bunker, and the Courier is asked by Ibsen to 'partition' the virus for Ibsen.

The Courier must find the virus on 3 terminals in 60 seconds to wipe it from the system. To do so, quickly enter each terminal and choose the only option one can. Then, if the text that shows up seems like a random string of letters and numbers, proceed to the next terminal. If one gets a taunting message on the second screen, choose the option to isolate the virus. The infected terminals are almost always in a row or close together in a group. The virus usually has one per section (such as 1 in the middle). If the player character does not get all 3 terminals in the time limit, they will have to speak with Ibsen again in order to receive a new countdown. Note that the virus can jump to the terminal Ibsen is standing in front of.

With a high enough Science skill (70), one can suggest partitioning the terminals when the virus jumps to it, giving read only access to the kernel administrator. This isolates the virus on that terminal permanently and leaves the player character with one fewer terminal to find should they fail.

With a Repair skill of at least 60, one can also repair the circuit breaker, located in a box on a wall on the western side of the room. Doing so results in the option to power down all but three of the terminals, interacting with the breaker again gives the option to restore power to all terminals. Note that interacting with the breaker may prove difficult, see bugs section below for more info.

The virus can be partitioned easily by saving immediately after Ibsen tells the player character it has jumped and after finding and isolating the virus. The terminals the virus jumped to will be consistent when reloading a save.

Behind the scenes
The behavior of the virus is similar to that of "Creeper", the world's first computer worm created in 1971.

Bugs

 * Prior to version 1.2.0.314 (update 3): the quest can get stuck into a state whereas it is rendered impossible to complete after using the Science (70) option, and isolating the virus on 3 consoles by partitioning over multiple runs. If the problem was originally triggered in an older version, the update will not make the quest completable, and the problem should be fixed by other means: loading an earlier savegame, using the G.E.C.K. or a mod.
 * Fix: In the G.E.C.K., find the entry HVHuntingVirusScript. Open it and change the line "if VirusTimer > 0 && NumberFixed==3" (without the quotes) to "if VirusTimer > 0 && NumberFixed >= 3" (again, without the quotes). Save the file to your Fallout: New Vegas/Data folder, and load it as you would any mod/DLC from the launcher. Talk to Ibsen to start the virus count, and check one of the already partitioned terminals. Ibsen will then announce the virus is purged, and the terminals will work.
 * After several tries a scenario arose where all 3 terminals had been found and isolated. This however did not cause Ibsen to react, and merely stated the Virus had jumped again a few seconds later. The next try was confusingly won after only 2 terminals had been isolated. The save exploit had not been used either.
 * Although it may be a glitch, it could be considered a rapid solution to purging the virus. If one finds a computer with the virus on it, rapidly isolating it three times will result in the virus being purged. Ibsen will say the virus had gone and one will gain access to information stored in the database.
 * Interacting with the circuit breaker box is only possible while being in third-person-view. The easiest way to access the interaction prompt is to stand close to the right of the breaker box, followed by turning south, and slowly moving the crosshair to the left until the prompt appears.
 * Using the breaker may not force the virus to the 3 remaining terminals, effectively removing this as a solution.