Salutations,
We wanted to throw together some helpful information and FAQ for the upcoming 4.0.0 patches and how the system will be evolving for Cataclysm. In this you’ll find what to expect during patches now, what you should expect as far as performance for bandwidth and of course how long it should take to get the patch installed. Please be aware as always this information is subject to change but we wanted to try and give you an idea of what to expect whenever the patches do go live.
When they do we will be changing the way we deliver patches and this will in turn change what the player base will see on that day. This will also change a bit on how we troubleshoot/address issues. However I’m sure we’ll be telling people to delete add-ons plenty for the 4.0.0 switch over, heh. At this time it is also possible that standalone patches may be slightly delayed behind the standard patching method. As such it is highly recommended that all players do everything they can to use the standard patching system to obtain these updates as we’re unable to provide an ETA for the standalone release period.
Now as the information below is quite a bit to take in, but in my belief that knowledge is power we’re going to deliver this in two ways. The ever popular TL

R version and the full detailed information for those techies out there that want to read a bit.
TL

R – Patch 3.3.x through 4.0.1
With the preparation for Cataclysm well underway and the fires of Deathwing growing hotter, now is the time to prepare for the future of the World of Warcraft. The patch and installation systems are undergoing significant changes and will now download and install at the same time. This will also allow you to play while patching if you meet the bandwidth requirements. There will be two patches to bring everyone up to 4.0.1 from the 3.3.x level. When the patch is released, players with the background downloader will see a few patches including a tools patch to get to 4.0.1 and it will take at least an hour in most situations for the patching to complete. (NOTE: This does not include download time and is purely the conversion process.) From this point forward, post 4.0.0 players will be using the “streaming” installation method and have the option to play while patching. We’re not announcing a date for the patches/installers however they are coming.
Full Detailed Info:
PATCH 4.0.0+ Information
- Background download 4.0.0
Presently, all players should be background downloading the data for 4.0.0 if they can to ease the transition on patch day.
The Size of 4.0.0 Background Download Stages 1-3:
Region Size
NA 4.9 GB
EU 5.3 GB
KR & TW 4.8 GB
- Patch up to 4.0.0 (Migration Patch)
This patch is a special patch which migrates players from the current 3.x layout to a new 4.x layout. This process may take over an hour, IN ADDITION to time spent downloading any data that the player is missing. Players will first see the downloader. The downloader will pull down any data they were missing from the background download, and then will pull down the FINAL STAGE of data (~70-100 MB, depending on your region).
Once all the data has been downloaded, the player will see the updater window. At this point, we are converting to the new 4.0.0 system and this will take some time. During this process, we are converting retail clients from “non-streaming” to “streaming.”
- Apply Tools Patch
Once the 4.0.0 Migration Patch is complete, the new 4.0 Cataclysm Themed launcher will appear – and the first order of business is to update it (as well as the downloader and updater.)
Tools patches are now much more seamless. Instead of kicking the player out and having the downloader and updater flash up on the screen, the update occurs in the launcher itself.
The Size of tools patch: ~19MB (PC), ~26MB (Mac)
- (Streaming) Patch up to 4.0.1
You are now ready to stream WoW! All data after this point will be delivered via the new “Play on Demand” patching system. The progress of the update (which includes any data that needs to be downloaded/updated), is displayed at the bottom. This is pretty self-explanatory, but players may click the “+” next to “New Cataclysm Launcher” for details. Once the “Setup” stage is over, the “Play” button will brighten up and become clickable. Clicking on it will launch the game and allow the player to log in.
- Player Enters WoW
The player should see the familiar Wrath of the Lich King login screen. If the player has entered the game before the patch download and application are complete, the download and update of the game will continue in the background. The time it takes to complete the download depends on how much data they must download/update, and the speed of their internet connection. Those factors may also have an impact on the play experience if the player encounters data that they have not already downloaded or applied.
The player may see blue walls, temporary low-resolution textures, or experience a delay while the required data is retrieved and applied. The player will see a couple of new UI elements in WoW related to streaming. While the player is downloading data, a radial icon will appear. Its color reflects the stage of data being streamed. If the player mouses over the PC icon, they will be able to see how much of the game has been downloaded.
*BANDWIDTH REQUIREMENTS*
• The download of players with more than 1 Mb/s will consist of three stages:
o Setup: Core game content is being prepared. You cannot enter the game at this time.
o Available: Major game content is not completely applied. You can play, however your game experience will not be ideal.
o Playable: Final game content is almost complete. You may experience a few game issues while playing at this stage.
• The downloader of players with less than 1 Mb/s will consist of only two stages:
o Setup: Core game content is being prepared. You cannot enter the game at this time.
o Playable: Final game content is almost complete. You may experience a few game issues while playing at this stage.
• The “Available” stage is missing for players under 1 Mb/s … it has been added to the setup stage. Players with low bandwidth must wait until the green section to play.
•
If a player is low bandwidth, a yellow triangle with an exclamation point will appear at the bottom of the Launcher. If the player clicks on this button, the Connection Info screen will pop up. At the top, the player will be notified that they have low bandwidth and so their streaming options have been limited.
• Players with low bandwidth may elect to override this limitation by going to the downloader preferences window (under options at the top of the Launcher) and selecting the “Allow quick play regardless of network speed” option.