From Glitch City Laboratories
|This article is a summary page for variations of certain glitches or phenomena such as Pokémon Cloning, glitch myths, beta elements, or a collective term for variations of glitch Pokémon which share similar names, sprites or other information.
Within the Pokémon games, error codes instead of error messages are sometimes used to refer to a particular problem, especially, after the launch of the Global Trading System in Pokémon Diamond and Pearl. Error codes are often more convenient than error messages and can take up less memory for documenting more errors than if the developers used text to inform the player of an error.
For error codes in the Global Trading System (or any other Wi-Fi service by Nintendo), the game developers ask players to refer to their local website based on the region his or her Game Pak was built for.
Error codes also exist in Generation I, however the purpose of these error codes are unknown, which in theory makes them beta elements.
In Generation I
The purposes of these error codes were never documented by Nintendo. They can appear in multiple ways through various glitches such as different variations of the Ditto Trick.
In Pokémon Red and Blue, error codes are displayed in the form of "X ERROR". In Pokémon Yellow however, they are displayed in the form of "X error". The exact reason for this is unclear, although the string "error" is used once in the game; if the player attempts to print out either the highscores for Pikachu's Beach or the Diploma but recieves a printer error, when he or she returns to the overworld he or she will recieve the text "PRINT error!".
In Generation IV
Error codes are used in the Nintendo Wi-Fi Connection service for areas such as the Global Terminal or when the player attempts to connect to Mystery Gift. If a connection fails, the game will give the player a five digit number (or sometimes a six digit number in non-Pokémon games) and suggests to the player that he or she can refer to the official Nintendo website for a detailed explanation of the error.
A player recieves a printer error (#2) within Pokémon Gold and Silver.
Within the Generation I and II Pokémon games (and any other Game Boy game which is compatible for use with the GameBoy printer), a total of four legitimate printer errors are used for when the player attempts to print visual data within the game (e.g. a Pokédex entry) but the printer cannot perform the task.
Below is information about the four possible error codes, regarding what causes them and how these errors can be ammended (as sourced by Nintendo )
||The batteries are empty.
||Insert new, working batteries into the hardware and then turn the power on.
||The universal game link cable is not, or incorrectly connected to the printer.
||The player should re-connect the link cable correctly.
||There is a paper jam.
||Carefully remove the Paper Jam (see the GameBoy printer manual for more information) 
||The ambient printer temperature is too high or low for the printer to operate.
||Attempt printing again at an appropriate room temperature.
It is notable that the game can crash if it attempts to manage a 'printer error' with an identifier greater than 03, although this should never happen within normal gameplay. Additionally, in Pokémon Yellow, if the player attempts to print out something directly from an NPC in the main map interface, if he or she recieves a printer error and returns, the dialogue "PRINT error!" will be displayed.
-  - Nintendo.com's page for diagnosing error codes for games on the Nintendo DS, Nintendo DS Lite, Nintendo DSi, or Wii.