The Tool Desk
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These are historical packages. In 2026, install the latest cumulative update offered for a supported Windows 11 release rather than manually installing a 2024 update, unless you are reconstructing or investigating a February 2024 system.
KB5034765 versus KB5034766
The two packages were separate cumulative updates for different Windows 11 release branches. They were not interchangeable simply because they shipped on the same day.
| Installed Windows 11 version | February 2024 package | Resulting OS build |
|---|---|---|
| 23H2 | KB5034765 | 22631.3155 |
| 22H2 | KB5034765 | 22621.3155 |
| 21H2 | KB5034766 | 22000.2777 |
Microsoft’s Windows 11 release information is available at Microsoft’s Windows 11 release information. The applicable package also depends on the edition, architecture (normally x64, or ARM64 on supported devices), and servicing channel.
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#1 Best Overall
- Get NVMe solid state performance with up to 1050MB/s read and 1000MB/s write speeds in a portable, high-capacity drive(1) (Based on internal testing; performance may be lower depending on host device & other factors. 1MB=1,000,000 bytes.)
- Up to 3-meter drop protection and IP65 water and dust resistance mean this tough drive can take a beating(3) (Previously rated for 2-meter drop protection and IP55 rating. Now qualified for the higher, stated specs.)
- Use the handy carabiner loop to secure it to your belt loop or backpack for extra peace of mind.
- Help keep private content private with the included password protection featuring 256‐bit AES hardware encryption.(3)
- Easily manage files and automatically free up space with the SanDisk Memory Zone app.(5). Non-Operating Temperature -20°C to 85°C
Check your Windows version first
- Press Windows key + R, type
winver, and press Enter. - Alternatively, open Settings → System → About → Windows specifications.
Do not choose a package merely by searching for a KB number. A later cumulative update can supersede the February package even when KB5034765 or KB5034766 is not shown by name.
The two exploited Windows vulnerabilities
CVE-2024-21412: Internet Shortcut Files
Microsoft classified CVE-2024-21412 as a Windows Internet Shortcut Files security feature-bypass vulnerability and reported exploitation in the wild. A specially crafted shortcut, link, attachment, archive, or similar content could weaken protections that normally warn before dangerous content opens.
A realistic attack generally involved user interaction: the victim received attacker-controlled content, opened or interacted with it, Windows security checks were bypassed or reduced, and the attacker then relied on another malicious payload or application. The flaw was not, by this description alone, a standalone remote-code-execution vulnerability.
Rank #2
- Solid state performance with up to 800MB/s read speeds in a portable drive. (Based on internal testing; performance may be lower depending on host device, interface, usage conditions and other factors. 1MB=1,000,000 bytes.)
- Back up your content and memories on a storage solution that fits seamlessly into your mobile lifestyle.
- Take it with you on your adventures—up to two-meter drop protection means this durable drive can take a beating. (Based on internal testing.)
- Secure it to your belt loop or backpack for extra peace of mind thanks to the tough rubber hook.
- From Sandisk, a brand professional photographers trust to take on assignments.
CVE-2024-21351: Windows SmartScreen
CVE-2024-21351 was another security feature-bypass issue, this time affecting Windows SmartScreen. SmartScreen is designed to warn about suspicious downloads and websites. Microsoft said attackers were exploiting a way to bypass a SmartScreen protection mechanism when a victim interacted with malicious content.
SmartScreen did not guarantee that every malicious file would be blocked, and exploitation generally depended on opening or otherwise interacting with attacker-controlled content. The exact chain could vary by campaign.
What “zero-day” and “exploited in the wild” mean
A zero-day commonly describes a vulnerability exploited before a fix was available. In this release, urgency came from Microsoft’s evidence of real-world exploitation, not just a theoretical proof of concept. “Exploited in the wild” does not mean every vulnerable computer was compromised, nor that exploitation required no user action.
Rank #3
- Easily store and access 2TB to content on the go with the Seagate Portable Drive, a USB external hard drive
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition no software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
Microsoft’s release description is at the February 2024 Microsoft Security Update page. Independent coverage reported that the broader release fixed two actively exploited Windows zero-days among 73 vulnerabilities: BleepingComputer’s February 2024 summary.
What the February 2024 Patch Tuesday total covered
Microsoft’s complete February 2024 Patch Tuesday release addressed 73 vulnerabilities across Microsoft products. That count included products such as Windows, Office, Exchange, and Windows Server; it does not mean that either Windows 11 cumulative update independently contained fixes for all 73 issues.
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1Clear out junk files and repair common Windows errors2Fix the driver behind crashes, sound loss and screen glitches3Repair Windows errors before they cause bigger problemsWhat each update delivered
KB5034765 for Windows 11 22H2 and 23H2
KB5034765 delivered the February security fixes and moved 22H2 to build 22621.3155 or 23H2 to build 22631.3155. Microsoft distributed it through Windows Update, Microsoft Update, and the Microsoft Update Catalog. See the KB5034765 support article for the release notes and documented issue.
Rank #4
- NEARLY 2X FASTER THAN OUR PREVIOUS GENERATION(8) – move 1,000 high-res photos in under 60 seconds(6) with up to 2000MB/s transfer speeds(2).
- IP65 RATING AND UP TO 3M DROP PROTECTION(3) – protects against spills and drops.
- POCKET-SIZED – fits easily in pockets and small bags.
- SPACE TO OWN YOUR AI CONTENT – speed and capacity to download your high-res clips and photo edits.
- 256-BIT AES ENCRYPTION(4) – helps keep private files secure with password protection.
KB5034766 for Windows 11 21H2
KB5034766 moved Windows 11 21H2 to build 22000.2777 and was available through Windows Update, Microsoft Update, and WSUS when the appropriate Windows 11 product and security-update classification were configured. Version 21H2 support varied by edition, so verify the exact edition and lifecycle status rather than assuming all 21H2 installations had the same support coverage. See Microsoft’s KB5034766 support article.
How to install the update
For a current computer, use the latest applicable cumulative update instead of deliberately installing these historical packages.
Windows Update
- Back up important files and connect the device to reliable power.
- Open Settings → Windows Update.
- Select Check for updates.
- Install the applicable cumulative update and restart when prompted.
- Run
winverto confirm the resulting build.
Microsoft Update Catalog
Use the Microsoft Update Catalog search for offline installation, staging, or testing. Select the entry matching the Windows version, x64 or ARM64 architecture, client or server product, and cumulative-update classification. Do not substitute a dynamic update or an unrelated package.
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- Easily store and access 5TB of content on the go with the Seagate portable drive, a USB external hard Drive
- Designed to work with Windows or Mac computers, this external hard drive makes backup a snap just drag and drop
- To get set up, connect the portable hard drive to a computer for automatic recognition software required
- This USB drive provides plug and play simplicity with the included 18 inch USB 3.0 cable
- The available storage capacity may vary.
Enterprise deployment
- Pilot the update before broad deployment.
- Test VPN, endpoint-security, disk-encryption, drivers, and line-of-business applications.
- Schedule restarts and maintenance windows.
- Report installation failures and verify that endpoints received a later cumulative update when the February KB is absent.
- Use Microsoft’s Security Update Guide for current replacement and vulnerability information.
How to verify installation
Graphical check
- Open Settings → Windows Update → Update history.
- Expand Quality Updates.
- Look for KB5034765 or KB5034766, or confirm that a later cumulative update is installed.
PowerShell
Run the command matching the expected package:
Get-HotFix -Id KB5034765Get-HotFix -Id KB5034766To check both at once:
Get-HotFix | Where-Object HotFixID -in @('KB5034765','KB5034766')If no matching hotfix exists, PowerShell can report that no matching update was found. That does not prove the security fix is missing if a later cumulative update superseded it.
Command Prompt
systeminfo displays installed hotfixes. On older installations, wmic qfe | findstr 503476 can search for the KB, but WMIC is deprecated; PowerShell is preferred.
Known KB5034765 installation failure
Microsoft documented cases in which KB5034765 reached approximately 96%, failed, and rolled back. Error 0x800F0922 was associated with the failure. Consult the official KB5034765 documentation for the release-specific status.
Safe recovery sequence
- Restart and allow any automatic rollback to finish.
- Check Settings → Windows Update → Update history and record the error.
- Ensure adequate free disk space, stable network access, and AC power; disconnect unnecessary external devices.
- Run the Windows Update troubleshooter if it is available for the installed release.
- Microsoft’s documented workaround involved removing the hidden
C:$WinREAgentfolder and retrying. Confirm that the folder belongs to the failed update operation before removing it; do not delete unrelated system files. - If the failure continues, test the correctly matched Catalog package or follow Microsoft support guidance. Do not manually remove servicing packages without a backup and recovery plan.
If Windows will not boot
- Allow Windows to complete its rollback.
- Enter the Windows Recovery Environment.
- Try Startup Repair.
- Use System Restore if a restore point exists.
- From recovery options, try Uninstall latest quality update.
- Restore an organizational image or backup if required.
Uninstallability varies with servicing-stack dependencies, later cumulative updates, and the device’s recovery state.
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Home users
- Confirm that Windows 11 is on a supported feature release.
- Install the newest cumulative update offered in Windows Update.
- Do not spend time manually installing KB5034765 or KB5034766 on a fully updated system.
- Maintain backups and keep recovery options available before major updates.
Administrators and security teams
- Prioritize exploitation status and exposure to malicious links, downloads, archives, and shortcut files.
- Inventory endpoints still running 21H2 or 22H2 and plan migration to a supported release.
- Replace obsolete deployment images and validate current hardware requirements.
- Use pilot rings, reboot controls, compliance reporting, and failed-installation remediation in Intune, Windows Update for Business, WSUS, Configuration Manager, or an existing RMM platform.
Controls that complement patching
Updates address the vulnerabilities but do not eliminate phishing or user-assisted attacks. Pair patching with user training, attachment and URL filtering, Microsoft Defender or equivalent endpoint protection, application control where practical, least-privilege accounts, logging and alerting, and restrictions on untrusted downloaded content.
Quick Recap
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