LR catalog cannot be opened because another application already has it opened.

[Pineconephoto]

I updated my LR catalog today because it was being very slow. After updating it still wasn't working correctly (not exporting photos) I am now unable to open my LR catalog to export wedding photos for a client. When I go to open my catalog I am getting notification  "LR catalog cannot be opened because another application already has it opened."      I have tried uninstalling and reinstalling LR, still having the same issues.

I read on another post to look for a file extension .lock  .. There is one on my external HD where I store my catalog. The post said to delete the .lock file and the catalog will be good to go. Just want to make sure I'm not going to corrupt my catalog or loose any photos/editing time if I do that!!!

[Rob_Cullen]

No. you will not corrupt your catalog. (Do NOT delete the catalog file with the extension .LRCAT)

(That is not to say that the Catalog may be corrupt by some other problem)

The .LOCK file is always present when a Catalog is 'open' in Lightroom. When you close/exit Lightroom correctly, the .LOCK file is removed.

If Lightroom shuts down by anything other than the correct method (eg. a computer crash, etc) then the .LOCK file remains and prevents you opening the Catalog. As in the error message- Lightroom 'thinks' the catalog is already open, when in fact it is not.

Delete the xxxx.LOCK file with the operating system and restart Lightroom.

[Pineconephoto]

Thank you!!!! I did delete the .lock file and was able to open my catalog back up!! But I can still not do anything else.. Not sure if it's the new update on my Mac and that is why it's not working? It's super slow/wont load selections and freezes up.

[Rob_Cullen]

I updated my LR catalog today

Do you mean you updated Lightroom?   And then had to update the Catalog in the 'new' Lightroom version?

Please give us your Operating System and Version Number.

Also copy&paste the first few lines of the Info from-  Lr Menu > Help > System Info.

And do you remember how or why Lightroom would have crashed or been closed incorrectly?

not exporting photos

So this is another problem. Why does it not export? Any Error messages? (exact wording please) How were you trying to export?

[Pineconephoto]

I just updated my Mac to Mojave 10.14. Not sure if that is having any reason with the issues?

I just updated Lightroom today. With all the issues I tried uninstalling and then reinstalling Lightroom, as well. Never had to update my catalog to the new version. Normally it proms me too. It will open Lightroom into the new update version, I have been prompted with the new tips from the update. but after is when I am unable to actually work in Lightroom.

It will load a couple photos in "Library" but if I go to scroll through photos or go to "Develop" It's just grey and never loads, just says "loading" Then it will crash and ask if I want to report crash to adobe. I did report a couple of the crashes.

There is no error message with exporting. (It never shows the exporting toggle in the top Left corner like normal) The file appears on the desktop (Where I am exporting too) But no files ever export.

Lightroom Classic CC 8.0

Lightroom Classic version: 8.0 [ 1193777 ]

License: Creative Cloud

Language setting: en-US

Operating system: Mac OS 10

Version: 10.14.0 [18A391]

[Rob_Cullen]

I now only have suggestions, not answers.

Could be the OS update? Maybe Graphics driver?

Try some of the suggestions in this link-

Optimize Lightroom performance

Or give Adobe Support a go.

Classic v8.0 is not a major update, so does not require an update conversion of the catalog from the previous version.

The file appears on the desktop (Where I am exporting too) But no files ever export.

This does not make sense! If the exported file appears on the desktop, what is meant by "no files ever export" ?