P: LrC 15.5 Video Files Issues (Windows)

Moderators, ​@Rikk Flohr_Photography, please merge with the bug report:

https://community.adobe.com/bug-reports-674/p-lrc-15-5-video-files-issues-windows-1635342/index3.html?sort=oldestFirst#comments

Adobe has acknowledged this bug with video in LR 15.5 on Windows:

https://community.adobe.com/bug-reports-674/p-lrc-15-5-video-files-issues-windows-1635342/index3.html?sort=oldestFirst#comments

The only known workaround is to roll back to 15.4.1. Add your vote and constructive comment to that bug report, and you’ll be notified when Adobe releases a fix.

Nikon Z5II MOV files (H.265, 8-bit 3840×2160/30p) work correctly in Lightroom Classic 15.4.1, but fail with “An unknown error occurred when reading the video file” in both 15.5 and 15.5.1. By contrast, MP4 files (H.264,1920×1080/30p) work normally. The H.265 files play normally in Media Player Classic. The problem occurs in a new Lightroom catalog and persists with GPU acceleration enabled/disabled and after clearing the video cache.

I have just come across this as well when trying to import DJI Mini 4 Pro mp4 files. I’ve always been able to import these in the past, H265 10bit format. Windows 11 (with additional HEVC codecs installed) Downgraded to 15.4.1 and it works again as it used to.

Interesting that this has been around for almost a month without official feedback from Adobe?

I can reproduce this same bug on my PC on both 15.5 and 15.5.1 - affects newer mobile phone videos as well as footage from my GoPro Hero Black 13. Downgrading to 15.4 fixes it so definitely not an issue with my PC setup. When will this be fixed???

This version 15.5 broke handling most video formats on PC for me. 15.5.1 doesn’t seem to fix it - anything on the horizon?

On import Lightroom Classic fails to generate the thumbnail preview and gives an "unknown error occurred while reading the video file" error and fails to import Nikon Z8 H.265 10-bit video clips.

Lightroom Classic 15.5 and 15.5.1
Windows 11 version 25H2 Build 26200.9278.
Camera model is Nikon z8

Step-by-Step Instructions:

1. Set Nikon Z8 to record video in H.265 10-bit (MOV) format.
2. Copied .mov file off camera card and to a computer hard drive location to eliminate an issue with importing for the CFExpress card.
3. Opened Lightroom Classic and selected Import. Navigated to hard drive location with .mov files. Lightroom Classic shows the file name. Instead of showing a preview the text “Preview unavailable for the this file” is displayed.
4. Check marked and clicked import
5. Import results window is next displayed with the following text. “Some import operations were not performed”. “An unknown error occurred while reading the video file (2)”. This is followed by a list including the names of the H.265 10-bit files that were not imported.
6. Closing the window shows the message “No photos in previous import”

Expected result: The video file should generate a preview thumbnail and import successfully, as it did in the previous Lightroom versions. Last version where this worked is 15.4.1.

Actual result is the file fails to load with unknown error. Have also noticed that in Library mode that LRc will display different error message when displaying previously imported H265 10-bit files. Assume that this is related to the import issue.

Current workaround: Reverting back to LRc 15.4.1 allows import of H265 10-bit video files generated by the Nikon z8. And limited play back in Library module. Have also confirmed that version 15.5 can import H.264 8-bit video clips generated by the Nikon z8. It is just failing to import H.265 10-bit. It also will not import H.265 8-bit.

The crazy thing is that this bug continues to be tagged with “Needs more info”(??). Really?

Bug Reports

Same issue here. Impacting my wedding workflow massively and 23days and still no fix!?!?!?!?