This is a brief tutorial to fix a corrupt Session file. Your Session file is a database file that helps to run your Session. The procedure is a easy, and without risk of losing images or image data. That said, always create a backup before performing maintenance on your data.
Fix A Corrupt Session File
It always happens when it is most inconvenient: when opening a Session you get a message that the Session database seems to corrupt and can not be opened.
At this point there is still hope. You click on Verify and Repair…
If this is what you get, the Session database file is lost. The text can vary (I intentionally screwed up here big time) but the color is red, and red is bad. What does this mean, what is the damage, and how do you recover? And last, is there a preventive measure you can take?
Note: if you have a backup of your Session file, restore it. If not, read on for repair.
I take you through some easy steps to quickly recover from this disaster. And although it is a proven method, be aware that you always perform this at your own risk. Backup before you start!
Anatomy Of A Session
Let me start with some basic knowledge about what a Session is. If you are already familiar with the basics, please skip this section and continue with the next.
On the file and folder level, a Session consists of four folders – Capture, Output, Selects, Trash – and a Session file in a single folder, the parent folder.
The Session file is a database file with the name of the Session. It shares the name with the parent folder of the Session. In my example, the parent folder is called Alchemist, and the Session database file Alchemist.cosessiondb.
The Session database contains information about the Session, like Session Favorites and Session Albums. Also, the Process Recipe you used last time in your session is stored in that database as is the Capture Name when tethering.
The four Session Folders – Capture, Selects, Output, and Trash – contain your images. These four folders are linked to four different functions in Capture One. In a brief description below I highlight the defaults for these folders.
The Capture Folder is where your images are stored during tethered shooting, but you can also import from a card into the Capture Folder.
The Selects Folder is where you move your best image to. Currently, with Albums and Smart Albums, the Selects Folder is not used very frequently.
The Output Folder is where Capture One stores the processed images. Of course, you can process to other folders, but this is the default.
The Trash Folder is where your images go that you delete. The folder is like a bin, that you can empty to permanently delete your images from your disk.
You can read more about Sessions in my series of posts that start with Sessions Explained.
When you open a session, Capture One opens the session database and finds folders, favorites, and other settings and applies them accordingly. When Capture One can not read the database properly it gives the corrupt warning, as I showed you ad the beginning.
Your first aid is to run a verification from the File menu > Verify Catalog or Session. Browse to the Session database file and open it. It will find the same error and provides the option to repair it.
It may succeed or it may fail. When it succeeds, open the Session and continue with your work. If it fails, replace the database with a new empty one to repair the Session.
Replacing the Session database file is a fairly simple operation with some unconventional logic in it as you will see in a minute. What you actually do is that you create a new session in the same location as the old one.
This sounds scary but the fun part is that existing images and their adjustments remain intact.
If you find this a scary exercise, try it with a dummy session first.
Important notice: Make a backup copy first, better safe than sorry.
The Process Step by Step
The following step-by-step procedure will fix a corrupt Session file.
- Close Capture One
- In Finder (Mac) or Explorer (Windows) locate the session and the corrupt session file inside it; check that the parent folder of the Session and the Session database file have the same name (this is the default but important in this procedure as one of them may have been altered, theoretically)
- This is a great moment for backing up your Session
- Select the Session database file with the .cosessiondb extension; change the extension, for example by adding _old to it, resulting in .cosessiondb_old
- Select and copy the name; you can do this by acting as if you want to change it (Enter on Mac, F2 on Windows) and hit Cmd+C (Mac) or Ctrl+C (Windows) to copy the name without the extension.
Note: this will assure that you create a copy with the same name.
- Memorize the location of your Session on your disk; for example, your Session’s parent folder is in the Picture folder. So far for the preparations. Now let’s get on with it and create a new Session database file!
- Start Capture One with the Alt (Mac) or Shift (Windows and some iMacs) key pressed to open it with the Recent dialog; choose New Session in the Recent dialog
- In the Name field, paste the name of the Session you copied in step 5
- For the Location, select the same location and create the Session; in my example, it was the Pictures folder but yours may differ
- Click OK to create the Session.
Now, go to the Library tool in Capture One. Your images are still in the Capture Folder, as are other images in the other three Session Folders as before you had a corrupt Session database file. Notice that any adjustments are still there.
Any Session Favorite and Session Album must be recreated. Check and select the Process Recipe again that you used for processing your images earlier in the session. And if you shoot tethered, check the Capture Name and counter.
You can regularly verify the Session database for errors the same way I explained at the beginning of the post. This will help to prevent unrecoverable errors. And a regular backup is also helpful. Note that there is no backup feature inside Capture One for Sessions, only for Catalogs, unfortunately.