iCloud Photos sync through iCloud app for Windows is stuck at a specific number of photos

Hello everyone!

I have a very annoying issue of my iCloud Photo library not syncing correctly and completely through an iCloud app for Windows. The situation in details is described below.

My environment:

• Windows 11 Pro 23H2, build 22631.3007 (latest public release)
• iCloud for Windows application, versions 15.0.214, 15.0.215 (the latest ones with the redesign), downloaded from the Microsoft Store

Preconditions:

• Number of photos and videos in my iCloud Photo library: 87799
• "Always keep on this device" option in Windows 11 is DISABLED for iCloud Photos, hence synced data are always thumbnails, not the actual full-size photos. It matters because this way the amount of available disk space is sufficient for the whole photo library to be synced as it was the case before.
• Amount of free disk space: 37 Gb
• Attempts to sync iCloud Photo library at this time: 4
• Number of photos actually synced EACH of these 4 times: 49267

What I did to try to resolve the issue:

• Disabled and then enabled iCloud Photo library sync in the iCloud app - ISSUE IS NOT RESOLVED
• Disabled iCloud Photo library sync, logged out of the iCloud app, then logged back into it and enabled iCloud Photo library sync - ISSUE IS NOT RESOLVED
• Disabled iCloud Photo library sync, logged out of the iCloud app, did an app reset through Windows 11 system settings (to delete all app data for iCloud), then logged back into the iCloud app and enabled iCloud Photo library sync - ISSUE IS NOT RESOLVED
• Disabled iCloud Photo library sync, logged out of the iCloud app, did an app reset through Windows 11 system settings (to delete all app data for iCloud), deleted the app itself, deleted every leftover file associated with iCloud app in any way from C:\Users\User\ directory, then downloaded iCloud app back from the Microsoft Store, logged back into it and enabled iCloud Photo library sync - ISSUE IS NOT RESOLVED
• Logged out of the iCloud app, removed my Windows 11 computer from my AppleID devices list, then added it back by logging back into the iCloud app and enabled iCloud Photo library sync - ISSUE IS NOT RESOLVED
• Tried iCloud Photo library sync using my Wi-Fi network with and without VPN (tried a couple of those as well) - ISSUE IS NOT RESOLVED

I've also been able to get logs for the iCloud app located under C:\Users\User\AppData\Local\Packages\AppleInc.iCloud_nzyj5cx40ttqa\LocalCache\Local\Logs, here is an excerpt from there which is repetitive. These same three lines appear in logs in the same order multiple times during the time when sync suddenly stops:

[26868 @ Mon Feb 12 2024 21:33:11.855] 27568 ERROR WP::CreatePlaceholderForPath CreatePlaceholders failed for : 0x8007007B: The filename, directory name, or volume label syntax is incorrect. 
[26868 @ Mon Feb 12 2024 21:33:11.856] 27568 ERROR WP::CreatePlaceholderForCloudFile Creating placeholder failed, hr=0x8007007b, signature=Af+SL9GJao2zNcA4wPvGEn88wP4f, serverFilename=tempFile.mp4 
[26868 @ Mon Feb 12 2024 21:33:11.856] 27568 ERROR WP::SyncDown::CreateOrUpdatePlaceholder Error 8007007b creating placeholder for asset signature Af+SL9GJao2zNcA4wPvGEn88wP4f: C:\Users\User\Pictures\iCloud Photos\Photos\tempFile.mp4

Also here is a screenshot of what it looks like after reaching a certain amount of photos I've talked about. After this amount is reached sync stops.

The interesting thing here is iCloud library sync works just fine on my iPhone but not on my computer. It started happening a few days ago out of nowhere, but everything was fine before that. My question is WHAT ELSE can be done to resolve this issue?

[Re-Titled by Moderator]