Halo: The Master Chief Collection Content Updates (2018-2019)
From Halopedia, the Halo wiki
Beginning in 2018, Halo: The Master Chief Collection was subject to a number of major content updates, the first of such since the initial wave of patches released in the 2014-2015 launch period for the game and aimed at fixing the game after the buggy original launch period. To see the original wave of updates and patch notes released in 2014-2015, see here.
Following the game's PC release and the addition of Halo: Reach in December 2019, a system of seasons were implemented to contain regular updates and bugfixes. As such, a list of seasons can be found here, and a list of title updates from 2019-onward can be found here.
These updates were announced as part of the "#FixMCC" project commonly requested by fans following the collection's notoriously buggy launch state, and subsequent silence. The fix was publicly announced in October of 2017 in an Xbox social stream, alongside the announcement of Master Chief Collection support for Xbox One X. The commencement of development of 4K UHD support for the collection was an opportunity for 343 Industries to delve into the game's core systems again and begin instituting a total rework of the game's backend systems and user interface to bring the game up to community standards.
In January 2018, a series of announcements were made about the FixMCC project; a legacy titles team was put together at 343 to oversee management of titles like MCC, and monthly updates began being produced as part of the team's commitment to transparency in communication. Additionally, the MCC Insider Program was launched to help provide regular feedback on the new updates and builds.
The initial FixMCC overhaul was released on August 27, 2018. While the patch notes are listed below, a comprehensive blog was also released detailing some of the changes made; this blog can be found here.
August 27 patch notes
August 27 patch notes
This update includes numerous new additions, features, improvements and fixes. Here’s a breakdown of the noteworthy changes included in the 8/27 update:
MENU & UI UPDATES
CUSTOM GAMES, FORGE, AND FILMS
HALO 2 ANNIVERSARY
The team is aware of and actively working on/investigating the following issues for future MCC updates:
Please keep an eye on the MCC Trello Board for the latest list of Known Issues and feedback areas that are under investigation by the team. In some cases, like “Corrupted Installation”, we have additional details to help troubleshoot and work around the problem should you encounter this rare issue.If you encounter a bug or issue, please let us know in the MCC forums here on Halo Waypoint.
September 20 patch
September 20 patch notes
HALO: CE CHECKPOINTS
This update includes numerous fixes across MCC with many big fixes aimed specifically at Halo: CE. Due to the scope of these changes, this patch will unfortunately invalidate mid-mission checkpoints for the Halo: CE Campaign. This means that after the update, you'll still have access to the missions you have currently unlocked but you'll lose your checkpoint save from mid-mission progress. We know this isn’t ideal but given the scope and impact of the bug fixes included in this patch, we felt it was an acceptable trade-off.
Quit ban code has been added and will be monitored to determine how they are enabled soon
Custom Games General
Forge & Films
October 3 patch
October 3 patch notes
Today, October 3, we are rolling out a small update targeting a very specific set of crashes some players have been encountering. We would like to thank the community for bringing these issues to our attention. Because of your reports in our support forums, the team was able to quickly identify the root cause and apply a fix. The full patch notes and helpful resources covering where to stay informed, leave feedback, and report issues is below.
October 10 patch
On the agenda for today, October 10, we have a new patch going live that will be addressing some errors and fan requested changes to gametypes within some playlists. The gametype changes today are based on community feedback for Team Snipers, Halo 3 Team Hardcore Doubles playlist, and HCE: Team Arena. As well, we will be loosening our matchmaking rules for both parties and ranks to help improve the experience for players finding matches. Some of you may be asking, “Well why did we need an update for playlist changes?” This is required any time gametype settings changes are needed but the specific settings aren’t already created and a part of the game. To make the settings changes we are required to add the new files to the game’s matchmaking file settings selection system and the only way is through a game update. 
Matchmaking Rule Changes
Ban Hammer Is LIVE
Since the September update, we have been tuning the rules behind the scenes for our auto-ban system to better address players who repeatedly quit out of matchmade games. Even though the automated version isn’t quite ready for prime time, the Ban Hammer definitely is. The team has recently issued our first wave of matchmaking suspensions to players who are actively and repeatedly quitting games.If you are worried that this could impact you, we would suggest not quitting out of games. Repeatedly quitting out of matches really creates a poor experience for the rest of the players in the game. Don’t do it. If you don’t like the maps or modes being offered, spin up a custom game with the settings you enjoy (check out the “Looking for Group” feature in the Official Halo Club to find like-minded players!).
November 19 patch
November 19 patch notes
January 16 patch
January 16 patch
Here are the key bug fixes included in the January update:
Below are a handful of known issues that the team is aware of with the January update. Each of these issues is on the radar so no need to sound the alarm when providing feedback. These issues were initially messaged back in early December, so hopefully players have had adequate notice and time to plan accordingly.
Due to work being done in the campaigns for both Halo: Combat Evolved and Halo 3, the mid-mission checkpoints for both HCE and H3 will be invalidated upon the installation of the January update. Please complete them prior to installing the patch or you will lose the checkpoint progress.
The team has found a bug in this update that causes Spartan Ops mission completion badges to not appear if they were earned in a previous version of the game (prior to the current updated build) or after the title is relaunched after they have been earned. The stats are being tracked appropriately and badges are awarded, but it's just that they aren't visibly appearing at this time. We are looking into a fix for this but wanted to inform players as this bug will be is in the January update.
In this build certain career stats may appear temporarily blank or not populate without first navigating to another stats page.
We have been investigating Achievement related queries players have been discussing in the MCC support forums for a while and have found an issue that is present with this update. Currently the ODST, Halo 4, and Halo 2 Campaign Playlists will not grant Achievements correctly when the playlist is started in a previous build, a player takes a new update, and then completes the Campaign Playlist on the updated build. We are investigating solutions for this currently.As a reminder, bookmark the MCC Support Page on Trello for the latest known issues and overall MCC development status.
February 13 patch
February 13 patch notes
Below is a complete list of the bug fixes that are included in today's update: