Lightroom Classic Freezing on Launch — macOS 15.7.1 (potential Dynamic Link / MediaCore Hang?)

Report · Oct 17, 2025

Dear Adobe Support,

I’m experiencing persistent freezing and unresponsiveness in Lightroom Classic on my MacBook Pro. The issue began suddenly a few days ago and continues even after reinstalling and testing multiple versions of the app.

Below are my system details and the steps I’ve already taken to troubleshoot. I've used Chat GPT to assit in diagnostics, and this summary write up. But please help. this is urgent. I'm a wedding photographer and behind on assignments, and this program will not open.

System Information

Computer: MacBook Pro (M1 Pro chip)
macOS: 15.7.1 (Sonoma)
RAM: 16 GB
Lightroom Classic Versions Tested: 14.5.1 (current), 14.4 (rolled back)

Description of Issue

Lightroom Classic hangs immediately after launch.
The interface grays out and becomes unresponsive — clicking produces the macOS “inactive app” sound.
When it does open briefly, the Library module fails to load previews or respond, while the Develop module works briefly before hanging.
Quitting the app causes another freeze, requiring a force quit.
The issue occurs even with a brand-new, empty catalog.

Troubleshooting Steps Performed

Catalog & Cache

Created multiple fresh catalogs (no photos) — still hangs.
Renamed or removed all *.lrdata preview folders.
Verified issue is not catalog-specific.

Preferences & Config

Deleted Lightroom preference files:
- ~/Library/Preferences/com.adobe.LightroomClassicCC7.plist
Created and tested a custom config.lua to disable sync and GPU.
Reset preferences using Option + Shift on launch.

Reinstallation

Fully uninstalled Lightroom Classic using Creative Cloud.
Reinstalled both the current and prior version (14.4).
Same result — hangs immediately after opening.

Terminal & Cache Cleanup

Removed caches and support folders:

~/Library/Caches/Adobe/{Lightroom, DynamicLinkManager, MediaCore} ~/Library/Application Support/Adobe/CoreSync ~/Library/Application Support/Adobe/Adobe Desktop Common
Rebooted and relaunched after cleanup.

GPU & Services

Launched with Shift held to disable GPU acceleration — no change.
Quit all Adobe background services (DynamicLinkManager, MediaCore, Adobe Desktop Service, CoreSync) before testing.

Crash / Behavior Notes

Activity Monitor shows “Application Not Responding.”
Sample process indicates threads blocked in:

MediaCoreIF DynamicLinkManagerConnection
Suggests Dynamic Link / MediaCore deadlock, not catalog or file corruption.
Develop module occasionally functions for a short time before hanging again.

Summary

Not catalog-related (new catalogs hang).
Not version-specific (14.4 and 14.5.1 both affected).
Not preference or cache-related (fully reset).
Not GPU-related (hangs with GPU disabled).
Likely cause: Dynamic Link / MediaCore / Creative Cloud background service issue on macOS 15.7.1.

Assistance Requested

Could you please advise on:

Whether this is a known issue with Lightroom Classic 14.5.x on macOS 15.7.1.
How to fully reset or reinstall Dynamic Link / MediaCore components independently.
What diagnostic or log files I can provide to help pinpoint the cause.

Thank you for your time — I’ve attached the most recent crash report and am happy to run any additional diagnostics you recommend.

Kind regards,
T

Report · Oct 17, 2025

Hi @Timothy274404869hhd, thanks so much for reaching out!
Quick question: when you try to open Lightroom Classic, do you see an error message? If yes, could you share a screenshot of it? That’ll help us understand what’s going on.
Dynamic Link issues often relate to video files. Could you try the steps in this guide and see if that helps?
https://adobe.ly/4qh1ndW
Appreciate your time on this!
Alek

*(If you mention me with an @, like @Aleke, I’ll get a notification and can respond faster.)*

Report · Oct 17, 2025

No error message when I open lightroom. I was actually on the phone with Lightroom Support, they were able to screen share into my machine and witnessed this strange behaviour. They said they've never seen this before.

I don't *think* i have any videos in my catalog. I don't work in video.