Killer Prioritization Engine blocks iCloud Sync

[eding1]

Hello! 

I use iCloud for Windows frequently to back up my photos and videos. However, I have recently been struggling with iCloud sync issues on my Windows 11 desktop with a Killer AX1675i Wi-Fi 6E network adapter. After reinstalling Windows and the application many many times, I finally figured out the problem.

When I try to open an image or a file that's stored on the cloud, I get the following errors: 

The file transfer will be stuck for a few minutes at 0% progress, then throw a 'Cloud operation was not completed before the time-out period' error. 

Additionally, I am frequently unable to log into the iCloud for Windows application. When I open the application on startup, I am greeted with a "an error occurred during authentication" error, that can only be resolved by repeatedly opening and closing the application. 

Lastly (and most egregiously), many times iCloud.com itself is even blocked. I am greeted with a "Connection Error iCloud encountered an error while trying to connect to the server."

When I turn off the Prioritization Engine in the latest version of Killer Performance Suite, all the problems go away.

I am able to access iCloud Windows, photos sync instantly, and the iCloud.com website stops being blocked.

This is clearly a problem with Killer/Intel's software. The problem (and solution) have been reported by many users across the internet:

https://www.reddit.com/r/iCloud/comments/1j7ux0o/comment/mkd6ldt/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button

https://www.reddit.com/r/iCloud/comments/1nr0yx7/icloud_for_windows_and_log_in_with_apple/

https://learn.microsoft.com/en-us/answers/questions/4105015/icloud-app-and-icloud-on-the-brower-wont-connect?page=2

The craziest part is that according to users on the r/Intel subreddit, the problem has been around since at least September 2023, and even worse, was supposedly patched already back in October 2023. 

This is a clear example of a bug and I'd appreciate it if the technical team could take a look at it and fix. Until then, I have to leave the prioritization engine disabled in order to get any functionality out of iCloud, both desktop and web. 

[JeanetteC_Intel]

Hello eding1,

Thank you for contacting Intel Customer Support regarding the iCloud synchronization issues you're experiencing with your Intel® Killer™ Wi-Fi 6E AX1675i adapter and the Killer Performance Suite.

I understand how inconvenient this must be, especially since you've already invested significant time troubleshooting by reinstalling Windows and the iCloud application multiple times. I appreciate you providing detailed information about the issue, including the specific error messages and your discovery that disabling the Prioritization Engine resolves the problem.

To help resolve this issue, I'd like to guide you through the following steps:

Step 1: Please ensure you're using the most current version of the Intel® Killer™ Performance Suite (Package version 40.25.1125.1924 | Driver version 24.10.0.4). You can download this from our Download Center or your system manufacturer's support website.

Step 2: Perform Clean Installation I recommend performing a clean installation of the Killer Performance Suite to ensure no conflicting files from previous installations are causing issues:

1. Download the latest Killer Performance Suite installer before beginning
2. Go to Windows Settings > Apps & Features
3. Uninstall any existing "Killer Performance Suite" entries
4. Restart your computer
5. Clear temporary files by pressing Windows + R, typing %temp%, and deleting all contents
6. Install the latest Killer Performance Suite version
7. Restart your computer again

Step 3: Verify Services After installation, please check that all Killer Network Services are running:

1. Press Windows + R, type "services.msc" and press Enter
2. Verify these services are set to "Automatic" and are running:

• Killer Analytics Service
• Killer Network Service
• Killer Provider Data Helper Service

Reference articles:

• How to Perform a Clean Installation to Solve Most Intel® Killer™ Performance Suite Issues
• Intel® Killer™ Performance Suite Service Not Running or No Killer Adapter Connected
• Download Intel® Killer™ Software and Drivers

In case the issue persists, please help provide the following important details so we can check deeper:

1) OS version and build.

2) Make and model of your system device.

3) BIOS version currently installed

• You may get these details above from the System Information by looking up "msinfo32"

4) Wireless adapters make and model.

• You may check from the Device Manager > Network Adapter > Wireless component > Properties (provide screenshot to of the "status" > Driver tab (driver version).

5) If previously working, what changes has been made before getting the issue?

While we work on a permanent solution, you can continue using iCloud with the Prioritization Engine disabled, as you've discovered. This won't affect your basic network connectivity but will disable some of the advanced traffic prioritization features.

If the clean installation doesn't resolve the issue, our development team may need to investigate this further as a compatibility concern between the Killer Performance Suite and iCloud services.

Please let me know the results after trying these steps, and I'll be happy to assist you further. If you continue experiencing issues, we can explore additional configuration options or escalate this for further technical review.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello eding1,

Were you able to check the previous post? 

Let us know if you have any questions. 

Best regards,

JeanetteC.

Intel Customer Support Technician

[eding1]

I was actually using an even newer version of the Killer Performance Suite software, as suggested by Intel Driver & Support Assistant, version 40.26.403.2234

However, following your advice, I went and installed the version you suggested, 40.25.1125.1924, after uninstalling 40.26.403.2234.

 

The photos refuse to sync and then end up timing-out.

After turning off priority engine and re-starting my computer, everything starts to work again.

 

I also checked that yes, the three Killer processes are running and are set to automatic.

After that, I decided to do a full-reinstall of Killer Performance Suite following your instructions.

I followed these instructions exactly:

1. Download the latest Killer Performance Suite installer before beginning
2. Go to Windows Settings > Apps & Features
3. Uninstall any existing "Killer Performance Suite" entries
4. Restart your computer
5. Clear temporary files by pressing Windows + R, typing %temp%, and deleting all contents
6. Install the latest Killer Performance Suite version
7. Restart your computer again

After following these steps but turning on Killer Prioritization Engine, iCloud does not work. After disabling Killer Prioritization Engine again, iCloud starts working again.

I will reply tonight with the OS version, BIOS version etc. 

[JeanetteC_Intel]

Hello eding1,

Thank you for the detailed update and confirming that disabling the Killer Prioritization Engine resolves the iCloud sync issues.

I'll wait for the additional system details you mentioned you'll provide tonight. Once I have that information, we can proceed with the next steps.

Thank you for your cooperation.

Best regards,

JeanetteC.

Intel Customer Support Technician

[eding1]

1) OS version and build.

Windows 11 Pro

10.0.26200 Build 26200

2) Make and model of your system device.

Desktop PC (custom built) 

Motherboard - ASROCK B760M Steel Legend WiFi

CPU - Intel Core i7-13700K

RAM - DDR5 6000 MHz 32 GB

Storage - 1.8 TB SSD (main drive), 1.8 TB HDD, 1 TB SSD. 

GPU - Intel Arc B580 Graphics Card

3) BIOS version currently installed

BIOS Version/Date American Megatrends International, LLC. 13.02, 10/8/2025

4) Wireless adapters make and model.

Product Type Killer(R) Wi-Fi 6E AX1675i 160MHz Wireless Network Adapter (211NGW)

(built into motherboard)

5) If previously working, what changes has been made before getting the issue?

This problem has been happening on and off for many months (don't remember exactly) but I finally figured out the cause recently. I have spent a substantial amount of time debugging this. 

Please let me know if there's anything else I can provide to help solve this problem. 

[JeanetteC_Intel]

Hello eding1,

Thank you for providing the comprehensive system details. This information is very helpful for our investigation:

• Windows 11 Pro Build 26200
• ASROCK B760M Steel Legend WiFi with Intel i7-13700K
• Killer Wi-Fi 6E AX1675i 160MHz adapter (211NGW)
• BIOS version 13.02 from American Megatrends

I appreciate you taking the time to debug this issue and identify the cause after experiencing it intermittently over several months. Your thorough troubleshooting efforts will be valuable for our analysis.

We'll proceed with further investigation of this issue using the system specifications and details you've provided. I'll share an update with you once we have more information or potential solutions available.

Thank you for your patience and detailed reporting.

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello eding1,

Please check your email for our private message requesting additional information that may help with further investigation of this reported issue. Be sure to check your inbox, as well as your spam and junk folders, as the message might have been directed there

Best regards,

JeanetteC.

Intel Customer Support Technician

[JeanetteC_Intel]

Hello eding1,

Did you have a chance to review the previous post and email?

Please feel free to reach out if you have any questions.

Best regards,

JeanetteC.

Intel Customer Support Technician