P: LrC 12.2.1 fails to start/launch or is extremely slow launching.

[Micke, Finland]

Hi,

LRC 12.2.1 is not starting anymore, just launches as a background process using significant amounts of RAM and CPU, but the visible window never shows up. 

I have already:

- Tried the alt-shift-click thingie.

- Tried logging out and in from CC.

- Wiping all data files from the computer and letting LRC create a fresh Lightroom folder and catalog file (sometimes it does that, sometimes it hangs before the folder is created). 

- Wiping all Adobe products with the cleaner tool and reinstalling just LRC.

- I have even formatted and reisntalled the computer (becuase it was a good time to do that anyway).

But LRC still fails. What to do next?

Edition Windows 10 Pro
Version 22H2
Installed on ‎17.‎03.‎2023
OS build 19045.2728
Experience Windows Feature Experience Pack 120.2212.4190.0

[GoldingD]

Update

A specific CACHE file may be at fault:

Mac: /Users/<username>/Library/Caches/Adobe/Lightroom/metrics.json

Win: C:\Users\<username>\AppData\Local\Adobe\Lightroom\Caches\metrics.json 

see : https://www.lightroomqueen.com/community/threads/lrc-cache-causing-crash-metrics-json-but-why.47409/

[GoldingD]

deleted

[David J Wood]

Yes - that's the setting that John is talking about. (Writing as a participant in the Lightroom Queen thread that John linked earlier).

[jrsforums]

I am on win11 & have had the 'Desktop app usage' switched 'on'.  I do not find this file, 'metrics.json' at the location indicated.  I checked my Synology backups and that file existed in 1/31/23 & 2/25/23, but was no longer there on 2/28/23 or since.  It was definitely not there when my system had problems (3/22/23).

[David J Wood]

There is certainly no proof that this is the cause of any issues other than for one Mac user who posted on the Lightroom Queen forums. It might not be linked to any other case or to the primary root cause of the "fail to start" issues on Windows. As John said, it's a correlation, not necessarily a demonstration of causation.

[MA9323]

Hi everybody,

Indeed, LR Classic works when this CACHE File (metrics.json) is deleted. Will see if this Problem will come back or not but at least LR works again and I know what to do. So anyone having this problem, try to delete 

Mac: /Users/<username>/Library/Caches/Adobe/Lightroom/metrics.json

Win: C:\Users\<username>\AppData\Local\Adobe\Lightroom\Caches\metrics.json 

@GoldingD and @John R Ellis thank you so much for that Info 🙂

[jrsforums]

On further testing, I found that the .json file disawhen LRC is active, reappearing when closed.  It seems to increase in size, slightly, each time. Since I don't have backups (LRC must have been open), I cannot see if it was getting really big or not.  Adobe seems to be looking at as I cannot access the setting in profile at this moment.

[Colton29057400wkqz]

I am having this exact problem as well on my Lenovo laptop with Windows 11.

[KR Seals]

Did you read Rick Flohr's post two down from yours?

[John R Ellis]

"Indeed, LR Classic works when this CACHE File (metrics.json) is deleted.

So that's two occurrences of a "poison" metrics.json file -- interesting.

"Will see if this Problem will come back or no"

Disabling the sharing of LR usage statistics with Adobe may avoid problems with this file. See here for how to do that:

https://community.adobe.com/t5/lightroom-classic-discussions/lrc-12-2-1-fails-to-start-on-windows/m-...

[John R Ellis]

A second Mac user reports that deleting "metrics.json" allows their LR to start:

https://community.adobe.com/t5/lightroom-classic-discussions/latest-version-won-t-launch-and-crashes...

[John R Ellis]

@Colton29057400wkqz, try deleting the file "metrics.json" as described here:

https://community.adobe.com/t5/lightroom-classic-discussions/lrc-12-2-1-fails-to-start-on-windows/m-...

Two Mac users have reported that fixes their problems starting LR.  Please let us know whether that fixes your issue (which may or may not be the same).

[bmhimages]

Same thing here. Deleting metrics.json makes Lightroom startable and I can work with it. It seems to bring to new problems (noticable slower, it does have problems with realising how many photos are in one folder and following problems with new imports), but still I can at least work with it for the moment. Huge relief!

So thanks for the help so far!

[John R Ellis]

A third Mac user reports that deleting "metrics.json" allows their LR to start:

https://community.adobe.com/t5/lightroom-classic-discussions/latest-version-won-t-launch-and-crashes...

[iefd47441994]

I can restart Lightroom on Mac after this procedure:

Preference File:

This procedure works for both Lightroom Classic and Lightroom Desktop.

If you are using Lightroom Desktop it can change the location of your local storage. Please review this setting after resetting preferences. 

Reset Procedure:

1. Close Lightroom.

2. Hold down [Alt/Opt]+[Shift] while restarting Lightroom.

3. Overwrite the Preferences when prompted by the dialog.

4. Close Lightroom.

5. Restart Lightroom.

[john beardsworth]

I am having the same issue on my Windows PC and deleting metrics.json does appear to allow LrC to restart.

Not sure whether it's related, but I'm currently unable to disable Desktop App Usage.

[John R Ellis]

"Deleting metrics.json makes Lightroom startable and I can work with it."

Good. Also disable the sharing of usage statistics with Adobe to (hopefully) prevent a recurrence:

https://community.adobe.com/t5/lightroom-classic-discussions/lrc-12-2-1-fails-to-start-on-windows/m-...

[John R Ellis]

"it does have problems with realising how many photos are in one folder and following problems with new imports"

If you're seeing the the message "No photos in selected folder", that's a bug introduced in LR 12.2:

https://community.adobe.com/t5/lightroom-classic-bugs/p-no-photos-in-selected-folder-mac/idc-p/13607...

The workaround is to roll back to LR 12.1.

[Keith Reeder]

You've already had several official responses.

[John1957]

Today on my PC running Windows 11,  I cannot open Lightroom Classic from the Creative Cloud Desktop. The other apps on the Desktop appear to be working. When trying to open Classic nothing happens. 

Can anyone help me with this?

John

[GoldingD]

If you log onto your computer using a different user account, perhaps the Admin account, does LrC behave?

[Bob Somrak]

Check this thread.  Especially the part about metrics.json file in the links

https://community.adobe.com/t5/lightroom-classic-discussions/lrc-12-2-1-fails-to-start-on-windows/td...

[John1957]

Thanks for yor help, how do i log in to the admin account?

[John1957]

Thanks for your help, I have looked and there is no metrics.json file, only a Local prefs.json file.

[GoldingD]

Thanks for yor help, how do i log in to the admin account?

By @John1957

see:

https://www.thewindowsclub.com/how-to-login-as-an-administrator-in-windows

https://www.alphr.com/login-as-admin-windows-11/

https://www.howtogeek.com/786907/how-to-log-in-as-administrator-on-windows-10-or-11/