Announcing Windows 11 Insider Preview Build 22449

UPDATE 7:10PM PDT: Recently, Windows Insiders in both the Dev and Beta Channels began reporting that Start and Taskbar were unresponsive and Settings and other areas of the OS wouldn’t load. We quickly discovered an issue with a server-side deployment that went out to Insiders and canceled that deployment. If you were impacted by this issue, you can use the following steps to get back into a working state on your PC.

Hello Windows Insiders,

Today we are releasing Windows 11 Insider Preview Build 22449 to the Dev Channel.

You may notice that this build number is higher than the Windows 11 preview builds you’ve been receiving. That’s because we’re moving the Dev Channel back to receiving builds from our active development branch (RS_PRERELEASE). This means the builds released to the Dev Channel no longer match the Windows 11 experience that will be released to customers on October 5th.

These builds are from the earliest stage in a new development cycle with the latest work-in-progress code from our engineers. These aren’t always stable builds, and sometimes you will see issues that block key activities or require workarounds while flighting in the Dev Channel. It is important to make sure you read the known issues listed in our blog posts as we document many of these issues with each flight. Because of being at the earliest stage of a new development cycle, you won’t see new features or major changes in these builds right away. These builds are also not matched to a specific release. New features and OS improvements from these builds could show up in future Windows releases when they’re ready, and we may deliver them as full OS updates or servicing releases.

For those of you who are new to the Windows Insider Program and flighting of OS updates – check out this article for how flighting works and what to expect in each of our channels.

What’s new in Build 22449

SMB compression behavior change

We first introduced SMB compression in Windows Server 2022 & Windows 11. SMB compression allows an administrator, user, or application to request compression of files as they transfer over the network. This removes the need to first deflate a file manually with an application, copy it, then inflate on the destination PC. Compressed files will consume less network bandwidth and take less time to transfer, at the cost of slightly increased CPU usage during transfers.

Based on testing and analysis, we have changed the default behavior of compression. Previously, the SMB compression decision algorithm would attempt to compress the first 524,288,000 bytes (500MiB) of a file during transfer and track that at least 104,857,600 bytes (100MiB) compressed within that 500-MB range. If fewer than 100 MiB were compressible, SMB compression stopped trying to compress the rest of the file. If at least 100 MiB compressed, SMB compression attempted to compress the rest of the file. This meant that very large files with compressible data – for instance, a multi-gigabyte virtual machine disk – were likely to compress but a relatively small file – even a very compressible one – would not compress.

Starting in Build 22449, we will no longer use this decision algorithm by default. Instead, if compression is requested, we will always attempt to compress. If you wish to modify this new behavior to return to a decision algorithm, please see this article: Understanding and controlling compression behaviors.

Please use the Feedback Hub to give feedback or report issues with SMB compression, using the Files, Folders, and Online Storage > File Sharing category.

Changes and Improvements

Reminder on Insider Participation & Settings

In our June 24th blog post, we announced that all Windows Insiders who had already been installing builds from the Dev Channel on their PCs up through June 24, 2021, would be allowed to continue installing Windows 11 Insider Preview builds even if their PC did not meet the minimum hardware requirements, with limited exceptions in some cases.

In support of the Windows 11 hardware requirements, the minimum requirement for previewing Window 11 builds in our Windows Insider Program was set to match the overall requirements for Windows 11, with the exception for TPM 2.0 and CPU family/model – the yellow column of the chart in the official blog post noted below.These PCs will continue to receive Insider Preview builds normally depending on which channel they have opted their PC into.

There were a set of PCs, already running preview builds in the Dev Channel up through June 24, 2021, that fell below the requirements,(please see the official Windows Blog post noted below for details). and failed hardware requirements beyond TPM 2.0 and CPU family.Those PCs, represented in the red column in the graph, had a limited exception to preview Windows 11 builds until general availability, and would then need to take action to go back to Windows 10 and would not receive future Windows 11 preview builds. Now that we are moving Dev Channel forward with newer Windows 11 builds than what will be released to customers on October 5th, those PCs have been opted out of flighting and likely see the message (shown in the official Windows Blog post) in the Windows Insider Program settings page. However, they will still receive Windows 11 Cumulative Updates leading up to general availability.

Important Insider Links

To learn how we made Windows 11, click here. You can check out our Windows Insider Program documentation here, including a list of all the new features and updates released in builds so far. Submit feedback here to let us know if things weren’t working the way you expected.

If you want a complete look at what build is in which Insider channel, head over to Flight Hub. Please note, there will be a slight delay between when a build is flighted and when Flight Hub is updated.

Before you update your machine, visit the Announcing Windows 11 Insider Preview Build 22449 | Windows Insider Blog today to view full details on new features, general changes, improvements, known issues and much more!