Friday, November 19, 2010

Friday: Lightroom 3 - BIG Crashes and Easy Fixes

Good Afternoon Everybody,

We are into our third day without Internet connectivity so today we are going to Plan B. My Verizon MIFI hotspot card will support up to 5 computers. The only problem is that I need to head to Best Buy to pick up the Wireless USB adapters. It will cost a few bucks but it will get us back up and running at my studio. You never know how much you miss or rely on the connectivity till you're disconnected.

Friday: Lightroom 3 BIG Crashes and Easy Fixes

LR3 Client Order In addition to our Internet issues around here we also had a few Lightroom 3 issues too. Here is the story. Jennifer had a portrait viewing appointment on Wednesday. The client loved the images and placed a nice order. She kept track of the order in Lightroom 3 - album images, extras for grandparents and friends, and additional portraits for family members. Everything was ready to go - or so she thought.

She closed out of Lightroom and made the obligatory LR3 backup of the files upon exiting. Yesterday she was going to begin working on the order and fired up Lightroom 3. That's when disaster seemed to strike - the file wouldn't open!

She received the message:

"Lightroom encountered an error when reading from its preview cache and needs to quit.

Lightroom will attempt to fix this problem the next time it launches."

Hit the “Read More…” link below to see how we fixed the problem.

The problem recurred every time Lightroom was re-opened. We kept getting the same message  and the previews were grayed out- not good.Preview cache - bad

"What's up here?" I thought. I tried to open the recent backup and it didn't open either! I could open some earlier backups though, but  they didn't contain the recent order information. So what do you do?

Preview cache - bad2It turns out it was a really  an easy fix. Just find the folder that contains the cached files and move it or rename it. I renamed it to BAD – etc. as shown above. Now click on on the *.lrcat file to restart LR3.  When Lightroom starts it will recreate the cache image folder – *.lrdata and shown below.

Preview cache - newThe time it takes to create the new folder will depend on how many Images were in it to begin with. A large catalogue will take some time. Since we create a new catalogue for each order, the time to regenerate the previews was not that long.

This is the second time we've had this happen and I’m not sure what causes the problem. We did set up all of our workstations so that we could open any Lightroom catalogue from any computer over the network. I covered how we did it right here at DPT a few months ago in my post "Lightroom 3 Jailbreak” - here is the link. I don't think that is the problem but who knows.

Anyway, knowing the easy fix will make it much less worrisome the next time it happens. I have to smile when I think of the Lightroom message, "Lightroom will attempt to fix this problem the next time it launches." If I can fix the problem that easily, why can't Lightroom diagnose the issue and do the same thing automatically?

Victoria Brampton LR3 Book I was lucky enough to find the fix in one of the Lightroom forums, but then I wondered if Victoria Brampton's new book, "Adobe Lightroom 3, the Missing FAQ" [link] would have the answer. Well, sure enough - after a little digging I found the solution right on page 258. Victoria runs a great blog, The Lightroom Queen, and is always a good resource for anything about Lightroom. I just received her new book this week and am looking forward to giving it a thorough read.


Hey gang, that's it for me today. I sure hope this Internet problem clears up before Sunday's KPPA webcast. We've got about 150 registered already for the FREE Print Review webcast this Sunday 1:00p.m. - 3:00p.m. EST. Hope you can stop by.

Everybody have a great weekend and If I don't see you Sunday, I'll plan to see everybody at the beginning of Turkey Week on Monday.

See ya' then everybody, David


  1. Good tip about the Lightroom thumbnail cache. Makes sense, I've read now and then that rebuilding the cache improves performance and works around some problems.

    One other important tip is that Lightroom (or at least the catalog you're working on) should always be closed down before doing an external backup of the catalog (i.e. copying it to an external drive. Otherwise you risk copying over an inconsistent catalog file that you can't open afterwards at all. Happened to me recently, thought I'd pass that along.

  2. Can someone tell me if the trash needs to be emptied of the BAD previews data before attempting to rebuild and optimize previews catalog? LR3 has been trying to create the new optimization for close to 40hours. Is that normal? I have a bit over 45,000 images in my library , almost all are RAW files.

  3. Thanks David. Last week, my Lightroom started giving me the Cache error message when it failed to backup.

    I re-named the cache folder just like you said and it worked perfectly!

  4. Thank you very much - you've saved my day with this tip!
    BTW your distributed access isn't the one causing the problem as I'm using a pretty basic setup with the only change being non-default catalog location (another local drive).