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LRC cache causing crash - metrics.json (but why?)

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Premium Classic Member
Jun 23, 2020
Lightroom Version
Operating System
  1. macOS 13 Ventura
I've been fighting with Lightroom Classic on my wife's mac for 2 weeks now. Basically, the program will not open. It hangs on the splash screen right after "Reading preferences" appears. Adobe support has been completely unhelpful. I have been on text chat and phone calls. I could bore you with the details but I won't. Also, the "normal" fixes like deleting the preferences files do not work. The issue is deeper. Fortunately or unfortunately, I was in software development for a couple of decades so I can think like a tester and developer.

A bit of context might help here. Over the last couple of weeks, I have managed to get LRC working again a few times - but it eventually returns to the same problem. The first time I got it going again was when I rebuilt my wife's mac from the ground up (format the drive, reinstall macOS, reinstall apps, restore LRC catalog). But a few days later, the same crash came back. The next time it started working again was when I did a manual delete of LRC. I did my research and found every folder that had anything to do with LRC and killed them all. Then reinstalled. It worked. Until this morning.

LRC was working fine when we went to bed last night. But this morning, once again, LRC would not start. So I started stepping through the various "hidden" folders, sequentially making a copy of each, deleting it and then trying to start LRC. If it didn't fix the crash, I'd restore that folder and move on to the next.

My tests succeeded when I nuked /Users/(name of my wife's computer)/Library/Caches/Adobe/Lightroom. So then my test process went into file by file mode (delete 1 of the files, reboot, restart LRC) and I found the culprit to be metrics.json. If I delete that file, LRC works (a new metrics,json is created when LRC starts). If I restore the old copy of it, LRC crashes. I've replicated it multiple times - metrics.json is what is causing the crash.

When I compare the bad/old version and the new version, the file size is wildly different. The new version is 16KB. The old/bad version is 6.67GB.

I guess the good news is that I now know how to resurrect LRC when this happens. The bad news is that after having this happen multiple times in the last 2 weeks, I know it will come back.

Does anyone have any thoughts on why metrics.json would become corrupt and/or so large that it's causing the startup crash?
Interesting. I just checked by main Mac system (also running Ventura and which is logged into my main Adobe account) and I don't have a "metrics.json" file in the location you specified. But on my old Mac system (Big Sur), which is logged into my test Adobe account, then I do have such a file (but it's only 8KB). I have no idea why the two systems differ, but.....thinking that "metrics" might be a clue, I checked my Adobe account settings under the "Privacy and personal data" tab and I discovered that for my test account I have the "Share information on how I use Adobe desktop apps" option enabled, but on my main account I have that option disabled. That setting may be nothing whatsoever to do with...
@Ed, Adobe tech support is completely untrustworthy for anything but the most routine issues. Many reports on the forums over the years of them saying anything to close out a call.

I think it's likely that until your finding got back to them via Jim, John, and posts on the Adobe forum, they were completely unaware of the cause of this issue. Three days ago, March 23, Adobe employee Rikk Florh (who is very competent and completely trustworth) posted on the Adobe forum that he was gathering all the reports on the forums about LR failing to start:

If Adobe had known of a workaround then, he would have published it.

I strongly recommend that no one waste their time with Adobe tech support for any but routine issues such as billing. Use this forum and the Adobe forums.
Amen, John!
I had turned off the account option Data App Usage yesterday and it was back on just now. I turned it off again. Let's hope Adobe is scrambling to fix this on the server side.
I checked just now and the option had been turned back on again! I turned it off (for the third time).
Mine has been staying off for the last few days, although I'm pretty sure they turned it back on a couple of days ago. It's very uncool on their part (and probably illegal in some jurisdictions) to not take "no" for an answer.
Mine has been staying off for the last few days, although I'm pretty sure they turned it back on a couple of days ago. It's very uncool on their part (and probably illegal in some jurisdictions) to not take "no" for an answer.
Mine was off long before these problems and has stayed off throughout.

I agree on the uncool part. However, if the data is fully anonymised then there is no GDPR breach, as fully anonymised data is out-of-scope of GDPR (recital 26 to Regulation (EU) 2016/679, with further amplification in article 11).
I was thinking that the illegality was that they were gathering data even though the user in question had specifically forbidden it.
I just found this thread. Any more news on this issue? I just moved to a new computer and initially, for about two times, I could open and close LR Classic to check to see if templates and such were working. Everything seemed to be in order and both times I closed down with checking integrity and optimizing the catalog. The backup file went where it was supposed to go. Since then I can not open LR. Not even the splash screen, just the blue circle going around and around. I thought I had not migrated my files properly and was getting ready to request help from the forum. First I'll try to read through this carefully and see what I can do with the information. It is now a week since anyone replied on this thread.
Any Updates?
Stephanie, I'll go read what you wrote.
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