Lightroom catalog cannot be opened because another application already has it opened

[brettl53394284]

This worked for me.  In addition to having the catalog issue, photoshop was crashing my entire computer to the blue screen of death.  After deleting this file it appears, so far I have no problems.  Thank you.

[neila12865118]

Had this happen to my Lightroom 5 library.  This worked for me.

Thanks so much!

[Guest]

Thank you so much!

[abbeym4537685]

the .lock file is only there when I open my lightroom, but I can't open the lightroom without the problem happening, did this happen to anybody else?

[Rob_Cullen]

What problem are you referring to?

"the .lock file is only there when I open my lightroom"-  correct, that is how it is supposed to appear.

Your Catalog is a file ending with the file-type suffix of  .LRCAT   Search yor computer folders to find your Catalog/s.

[rodrigop15362291]

It worked for me too, thank so much for you help!

[VironX]

I have the same problem, I just deleted the .lock file but it got even worse. My LR was able to run though it only showed me the "cannot open catalog" window, but I couldn't even open it after I removed the .lock file, and it just popped up the window which read "Adobe Photoshop Lightroom has stopped working". Then I put the .lock file back, and it went back to the initial "cannot open catalog" window. Did I miss any steps?

[Patricio Murphy]

In theory it should work with you just deleting the .lock file (and ONLY the lock file), it does for me. I'm puzzled because I've been using Lightroom for years and never ever had this issue, now I have to remove the bloody .lock file evry time I use the thing! Can't believe Adobe doesn't fix this.

[Rob_Cullen]

VironX,

The error message for the "Lock File" problem is very specific about- "....another application has it open..."

The Lock file must only be deleted when Lightroom is closed and not running.

Any other error messages would not be referring to the "Lock File" situation but some other problem with the Catalog.

Can you be more specific with the exact error message, and report your Version numbers for Lr and OS?

Patricio_Murphy,

The use of the Lock File to prevent multiple versions of the Catalog being 'opened' has always been part of Lightroom, and millions of users never have this problem- there is nothing really for Adobe to "fix". But your problem certainly is annoying and a cause and answer would be very helpful for you.

Are you 'Closing' Lightroom down in a correct manner? (eg. File>Exit)

Are you creating a Backup of the Catalog when you 'Exit'?

Are you allowing sufficient time for Lr to close entirely?

Does your Folder where the Catalog is stored have full Read/Write permissions?

This forum thread is very long- You both might benefit by starting a new post, where more people will see your post, and with your question add more details about your systems. (and screen-clips are helpful)

[VironX]

It says "Lightroom catalog cannot be opened because another application already has it opened. Quit the other copy of Lightroom before trying to launch." But I have no idea about where might my catalogue be opened except in LR. (and I'm wondering if this message has something to do with LRTimelapse which I've installed for couple months)

I use 6.10.1 version in Windows 7 Pro (64-bit), but I've never encountered with such situation before.

[Rob_Cullen]

VironX,

I doubt very much that LRTimelapse has anything to do with the error. LRTimelapse does use Lr to Catalog and Export photos, but-

The error message- "...cannot be opened because another application already has it opened..." is cryptic to some extent, and it always means that Lightroom "thinks or believes" that the Catalog is 'Open' already (although Lr is not running) and so refuses to start or open the Catalog again.

 Lightroom "thinks" it is 'Open' because there is a .LOCK file existing in the Lr folder location.

The "Correct Answer" by DW_Harrison in Oct2008 is still the Correct answer for this error message.

[VironX]

Sorry for replying late. I've uninstalled LRTimelapse but it didn't solve the problem, and deleting .lock file just resulted in "Adobe Photoshop Lightroom has stopped working" window again. Now I wonder whether it is possible to open my original catalogue after reinstalling LR. I don't even know could my catalogue be opened again...

[VironX]

By thw way, I browsed the code of my catalogue and found that all my edit data of this year was lost. I'm not sure if this means I might not able to recover them for good even if the catalogue problem is fixed.

[Rob_Cullen]

VironX,

If a Catalog did open for you, and you find missing edit data, then the most likely situation is that you opened an old Catalog, and not the most recent one.

It is still possible that your most recent Catalog still has a .LOCK file associated with it and therefore refuses to 'open'.

Search your entire computer for  Catalog type files, ending with the file-type of .LRCAT, and report what you find.

I note you are using 6.10.1.  It might also be worth installing v6.14.

The full install of v6.14 can be found here in the '2015 Apps', and {Lightroom 6} shown here is  Version 6.14 in this download.-

https://helpx.adobe.com/download-install/kb/creative-cloud-previous-version-apps-download.html

https://blogs.adobe.com/lightroomjournal/2017/12/6-14-now-available-last-perpetual-update-of-lightro...

[VironX]

Yes I found another catalog in another folder, and it seemed to have kept my more recent edit data. I think that folder may result from the reinstallation I did several years ago. Though I still can't open my LR after replacing this catalog with the older one, the catalog can be imported in my friend's LR whose version is later (2017 version if my memory serves me right), and thus I still can edit my photos based on my past data. On the whole, it's a good news that my data are not lost, but yeah I think it's time to update.

Thanks so much for your help!

[Patricio Murphy]

RE: Does your Folder where the Catalog is stored have full Read/Write permissions?

Seems this was the issue. Thanks. I don't recall setting the folder as Read Only, but then Windows does things...

Thanks again!

[daveg77118272]

Thank you!

[teris80629004]

THANK YOUUUUUUUU!!!!!!!!   Omg   I was geeking out!!!!   You are the best    💗💗💗

[HeatherPowellPhotographer]

Brilliant! That worked. 

[edagustin]

Oh my God, THANK YOU!!! This worked for me! I sincerely appreciate this information as I was in total freak-out mode! Thanks again!

[joenancym]

This worked for me. Thank you.

[david_t_21]

Thank you so much!!

[SrryBud]

I am having the very same issue and have followed the instruction as given, but upon deleting and reopening Lightroom Classic the LOCK file reappears leaving me unable to open LR. So what would I do to either unlock it or make it go away permanently? Also I tried reinstalling LR with no succes nonetheless.

[dj_paige]

Yes, when you open Lightroom Classic, a .LOCK file is created, and normally it goes away when you close Lightroom Classic. So under normal operation, you don't have to worry about this. Only when Lightroom crashes or the computer crashes do you have the problem where Lightroom can't open because the .LOCK file didn't get deleted, and then manually deleting the .LOCK file is the solution.

[SrryBud]

Thank you, that I understood, but what's happening to me is: I start LrC the message appears and the LOCK file appears. I close LrC it disappears leaving me no choice but to delete the LOCK file while LrC is running. So I do that but then when I try starting LrC again the Lock file reappears leaving me at the start of the process. So how do I do this properly?