Are You Getting The Lightroom Catalog Size is More Than 4GB Message?

In Lightroom, Photography by Matt K39 Comments

In the latest update of Lightroom CC, there’s a message that pops up if you try to back up your catalog. The message tells you that your catalog is over 4GB and that it’ll be zipped when backing up. The message box looks something like this.


But My Catalog Isn’t Over 4GB?!

If you’re wondering why this pops up even if your catalog isn’t over 4GB, you’re not alone. I’ve gotten a ton of messages over the last couple of weeks asking about it. So what gives? Well, it’s kind of an unintended feature 🙂 (I think that’s code word for bug). It seems that it pops up for everyone, regardless of catalog size. But I do know it’s been fixed already, and will ship out in the next Lightroom release.

But What If My Catalog is Really Over 4GB?

Well, if your catalog really is over 4GB then it’ll be zipped up in to an extractable archive (AKA. Zip File). But unless you’ve never downloaded anything off the internet before, your computer probably already has software to extract those zip files so I wouldn’t worry too much about it. But if you don’t have a zip file opener, the dialog box actually gives you a couple of suggestions.

I know on the Mac it’s automatic and when I download something, it automatically expands the zip file for me. And whenever I’ve used a PC, it seemed to have one built in as well.



  1. Angela

    What about deleting some old backups? How long would you recommend that we keep our backups?

      1. Ken Elliott

        You might want to consider keeping at least 2 copies, just in case the file becomes corrupt. I’m an old IT guy, and I keep the last 4 catalog backups. You never know when a bug will wreck a backup, and it’s good practice to have several.

          1. Steve

            I’m with Ken and Kent on this one. Even if the integrity of a file is tested when it’s written, there can be hard disk problems that corrupt it later on. It’s better to err on the side of caution when it comes to backups, especially ones as important as your catalog. At a minimum I would write my backup to my primary and backup photo disks immediately if I was only keeping one version.

        1. Kent Rebman

          I’m an old IT guy, too, and I concur, ‘integrity test’ or no. I’ve seen plenty of tested backups of things turn up lame, so to speak. Disc space is cheap and the backups are pretty small. It’s the previews that are eating me out of house and home. 😉

  2. Robert Sachs

    Thanks Matt,

    I was starting to get concerned when I saw the message before backing up. It would have been nice for Adobe to give us a heads up.
    Leave it to Matt to clear things up.


  3. Wayne

    I was getting it until I checked the ‘Don’t show again’ button. Thanks for letting us in that it will be fixed soon.

  4. Tim

    Thank you. I was ignoring it when it came up, but now I’ll smile as I ignore it 🙂

  5. Mike Rodriguez

    Sort of related question, Matt: Do you ever delete your cached previews (the [catalogname] Previews.lrdata file)? Noticed the other day mine has gotten sort of large. I’m guessing a lot of those previews are old. I know it would probably mean going back and waiting for others I want to rebuild, but, maybe worth it to knock the size down a bit?

    1. Author
      Matt K

      Hey Mike – I never have, but it’s not a bad idea. Alternatively you could select photos that are old in the Library module and go to Library > Previews > Discard…

  6. Barbara Clayton

    Wish I’d come here first! Just spend hours yesterday trying to resolve and splitting my catalogue into three bits. Still gives the message and I’ve probably messed up my previously good system. Expect better than this from Lightroom but thanks for your info – you saved today for me!

  7. Tom Irvin

    Just got the message last night and it freaked me out a bit. Thanks for the updated info, Matt

  8. Bruce Himelman

    I just got the same message and since it backed up the catalog I was not overly concerned. Matt: On another note I would appreciate it if you can get someone at Onone to look at my email from Dec 22 to support. My onone photo 10 will no longer work. I downloaded twice and it still will not load. Thanks. Happy New Year!!

  9. Keith Preston

    I got that message and decided to ignore it as a bug in the update. As expected, Matt is on to it! Happy New Year Matt!

  10. Lillian Rodriguez

    Wow, thanks for clarifying this! LR has been quite unstable lately between the “Over 4GB” which I’ve tried to fix by deleting unused images without making much of a dent. Hope they fix the bug soon. Happy New Year to you and yours!

  11. Walter Zutzchek

    I’m glad to have found this forum – I wouldn’t have expected a bug. Some very worthy comments in here, much better than many sites.

    My last BU, compressed, was a mere 270MB, while the catalogue itself was about 2.3 GB, for around 160,000 files kept on the iMac and on two external HDs. I’ve added but a drop lately, and now get this message (even after optimization) – but I can’t possibly have more than 2.4GB – in fact, saved just now it’s 2.32GB. A couple of times I started the backup procedure while quitting LR (despite the message), but aborted it (had to force-quit LR) when it seemed to hang.

    So does this mean that, until the bug is fixed, I can’t make a compressed backup (however big LR thinks my catalogue is), and can only back up the catalogue itself, say, on an external HD?

    1. Author
      Matt K

      Hi Walter – it doesn’t change anything about functionality. The backup still works fine. The only “bug” is that the message appears for everyone, when it should only appear for those with Catalogs over 4GB.

  12. Kirill Voloshin

    With Time Machine and other universal backup solutions that we normally use, why would we need a special backup feature for Lr at all? I can recall one time that I had to roll back to my earlier Lr catalog (after messing up my folders by mistake) but I easily accessed it with Time Machine.
    Is it at all useful? In what situations?


    Matt you are amazing and not hide anything. His teaching is perfect. Vocêdeixa all natural, it’s your nature. The currency of Brazil here shit, we have to multiply by four. I’m going to buy their products.
    Hug and success always.

  14. Pingback: A New Lightroom Update - Matt K

  15. FramedByMartin

    Hey MattK,

    is it possible that the 4GB FileSize Warning is coming up just in case you use an older FAT32 harddrive or something that can not store larger filesizes than 4gb?!

Leave a Comment