When you go to install the Lightroom Classic update, your existing Lightroom catalog is going to go through a significant upgrade process.  This process WILL take longer (even a lot longer) than you are used to.  This is because Adobe is compressing the Develop History and Metadata values in lrcat. This is expected to improve the overall responsiveness of Lightroom Classic CC.  But it does take some time — Don’t Panic.

What is a Catalog?

Your catalog is your database that tracks the location of your photos and all of the information about them and their adjustments.  If you edit photos, apply ratings, or organize with keywords, for example, those changes are stored in the catalog. Remember, your actual photo files themselves are not stored in the catalog.  When you first launched Lightroom, it created a new catalog, when you go to upgrade it will try to open up the last catalog you were using.  This is where the upgrade occurs.

Manually backup

Your catalog contains A LOT of effort.  All those edits took time.  I strongly suggest that you backup your existing catalog a few different ways BEFORE upgrading your application.  In theory, Lightroom Classic CC will create a new copy of your catalog, so your Lr6 catalog remains intact.  But a little caution is still a good idea.

Find the Catalog

First, locate the catalog file and manually copy it to another disk or cloud-based location. By default, Lightroom saves catalogs in the following folders:

• Windows: \Users\[user name]\Pictures\Lightroom
• Mac OS: /Users/[user name]/Pictures/Lightroom

If you’ve moved your catalog and can’t find it, just search for “lrcat” in the Explorer (Windows) or Finder (Mac OS).  It is possible to have multiple catalogs for different clients or projects, so be sure to back them all up.

Backup in the Application

It’s a very good idea to get in the habit of letting Lightroom backup your catalog automatically every time you quit Lightroom.  If you turn this option on and launch the old Lightroom first, you can invoke an application backup. Remember, backing up your catalog does not back up the photos that it references.

Make the Upgrade

When you are ready to upgrade, download and install the latest version of the application.  Remember the upgrade to Lightroom Classic is only available to Creative Cloud subscription members.  When you launch the Lightroom Classic application and open a catalog from an older version, Lightroom upgrades the catalog automatically.

1. Launch Lightroom Classic
2. If the catalog you want doesn’t open, choose File > Open Catalog.
3. Navigate to the old catalog.lrcat file that you want to use, and then click Open.
4. You may be prompted to relaunch the application.  If this happens, click Relaunch to close the current catalog and restart Lightroom.
5. Click Upgrade.

Remember, this upgrade process is expected to take a significant amount of time, especially on larger catalogs.  Be patient and let the project finish.  If working on a laptop, make sure to plug in for uninterrupted power. Lightroom is reorganizing the data in the catalog so it can be retrieved faster.