Also known as trashing the prefs, this is the act of forcing Lightroom to create a clean preference file in the hopes that it fixes whatever strange Lightroom problem you might be having. The preference file is where Lightroom stores all the settings you configure in the Lightroom > Preferences (Mac) or Edit > Preferences (Win) dialog. Along with all those settings Lightroom stores other data such as the location of your catalog file and which catalogs you recently opened among other things.
If Lightroom, or if your entire system, crashes shuts down unexpectedly this preference file can become corrupted, which can lead to problems ranging from more crashing to Lightroom not starting to all manner of odd and unexplainable behaviors. Sometimes a fresh do-over is just what the doctor ordered!
Here’s the basic steps:
- Open Lightroom
- Go to (Mac) Lightroom > Preferences or (Win) Edit > Preferences, and make a note of all your settings in your head or on paper. You’ll need to reconfigure those later.
- Close Lightroom.
- Navigate to the preference file (locations listed below) and delete it.
- Restart Lightroom and reconfigure preferences.
When you restart Lightroom a fresh clean preference file will automatically be created taking you back to the default settings. Important: Lightroom stores the location of your Lightroom catalogs in the preference file, so when the new preference file is created Lightroom will no longer know where your catalog was located. It will simply look to the default location for catalogs and open the one it finds there or create a new empty catalog, which can be confusing. Make sure you know where your catalog is stored before you trash the preferences by going to (Mac) Lightroom > Catalog Settings or (Win) Edit > Catalog Settings and check the General tab to see its location. If the wrong catalog opens go to File > Open Catalog and navigate to the right one.
Here’s where you will find the preference file on different operating systems:
On Mac, open Finder and navigate to the [ username ] \Library\Preferences folder, drag the com.adobe.Lightroom[VERSION#].plist to the Trash. If you don’t see the Lightroom plist file then you may be looking in the wrong folder (don’t go to Library/Preferences, go to [ username ] \Library\Preferences).
Note for Lion users: Apple made it harder to find that Library folder. Here’s how to track it down: http://kb2.adobe.com/cps/909/cpsid_90947.html
On Windows Vista and Windows 7, open Windows Explorer and navigate to the Users/[username]/AppData/Roaming/Adobe/Lightroom/Preferences folder, delete the Lightroom [VERSION#] Preferences.agprefs file.
On Windows XP, open Windows Explorer and navigate to the Documents and Settings/[Username ]/Application Data/Adobe/Lightroom/Preferences folder, delete the Lightroom [VERSION#] Preferences.agprefs file.
Note to Windows users: sometimes Windows likes to hide folders from you (for your own protection), so a shortcut to the Preferences folder is to open Lightroom, then go to Edit > Preferences > Presets and click the Show Lightroom Presets Folder button. This will open Windows Explorer to the Lightroom folder (listed in the path above) that holds the Preferences folder.
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15 Comments
This tip really saved my bacon. A power failure corrupted my LR catalog location, and deleting the Preferences file seems to have given me a chance at a fresh start. Many thanks!
Glad to hear it!
Before I go in and start playing around, I need to know if this will help me with my problem. I just recently upgraded to LR 2.7 from 2.6. All was working fine in 2.6. Now the only image that prints out correctly is one that is set to print at 8×10. If I select 11×14 as my cell size to print, the image prints at 7×9. Same if I select 4×6. Something is stuck some where but as I said would like to know if messing with my preference file will help me>
Well, it won’t hurt and it is free, but in my experience, most printer related problems boil down to the printer driver. Replacing the preferences is a good first step and fixes a lot of odd problems. If it doesn’t solve the problem in this case the next thing I would do is uninstall/reinstall the latest printer driver.
Thx Rob for replying to me. I tried both and no luck. It prints fine from CS3 so it is LR 2.7. Any other suggestions would be welcomed. It’s almost like it’s stuck on a setting some place. I’m on SP 2. Is it possible that I need to upgrade to SP3 in order for it to work properly?
I tried all I know and nothings works so I reinstalled 2.6 and it prints fine. Thx for your time.
The tip to find the preference file, since it is hidden in windows, was priceless.
Thanks
I was pulling my hair out over this, but thankfully was directed to your instructions here. Whew! Thank you so much!
The LR3 error I was getting was “?:0:Attempt to Compare number string” and could no longer access the Develop module. Deleting the Preferences file fixed it!! The step by step instructions here are GREAT! Thank you!!
None of this worked! I found the file, deleted it and it still shuts down – usually when exporting, printing, publishing – but now it’s even shutting down while I am editing… I am using 3.6 version and have even uninstalled and reinstalled the entire program.
Any other suggestions?
Have you tried creating a new catalog, and importing a few test photos into that to see if the problem continues or goes away?
I want to make you a donation. You saved my day!
Happy to help!
Saved my life! Nice work and everything started exporting properly after a Windows 8 upgrade.
Thank you so much! That is a really clever post! I couldn’t get the info to understand why Lightroom was not showing my virtual copies. In you blog I found it! Thanks man!