Download and use Find Any File to search for a file named "Library6.iPhoto". It's a file that is in very iPhoto library. FAF can search areas that Spotlight can't, like invisible folders, system folders and packages. If there's another library on your hard drive FAF will find it.
You can also try the following on the restored library:
Starting over from scratch with new library
Start over with a new library and import the Originals (iPhoto 09 and earlier) or the Masters (iPhoto 11) folder from your original library as follows:
1. Open the library package like this.
2. Launch iPhoto with the Option key held down and, when asked, select the option to create a new library.
3. Drag the subfolders of the Originals (iPhoto 09 and earlier) or the Masters (iPhoto 11) folder from the open iPhoto Library package into the open iPhoto window a few at a time.
This will create a new library with the same Events (but not necessarily the same Event names) as the original library but will not keep the metadata, albums, books slideshows and other projects.
Note: your current library will be left untouched for further attempts at a fix if so desired.
After getting the library back to where you want it go thru a coupld of Time Machine backups and then restore one of them (using the Keep Both option) and check the restored library to make sure it works as expected and has all of your photos. Then do the same maybe once a month just to make sure TM is working as advertised.
Hello Old Toad, I just went into the photo library that shrank from 172 GB to 20GB. When I try your method going through the package content I only find a LINK called masters but I find a folder called "Old Masters". But that folder is empty (0 Byte) although it says in the 2014 folder (=pictures from last year) 2525 files. Do you have an idea how I can restore those old masters files with FAF ?
When I tried to restore all lost files with Data Rescue, I got 160GB, but once I went through those with photo sweeper only 52 GB are left and of many many pictures, there is only the thumbnail and not the hi-res original, as described in this threat How to fix lost connections to original high-resolution pictures in iPhoto and how to import an iPhoto Book from one iPhoto library to another
I find a folder called "Old Masters".
You are victim of a bug in iPhoto 9.6 that happens when there's an interruption of the conversion process. I don't think you can restore the library at this stage. But check to make sure the Master's alias is truly an alias see where it takes you. If it's to the Old Masters folder delete the alias and rename the Old Masters folder to Masters. Then use the free, demo version of iPhoto Library Manager to rebuild the library as described below. It's a long shot but worth a try particularly if the Masters folder is really an alias pointing to the Old Masters folder.
Using iPhoto Library Manager to Rebuild Your iPhoto Library
1 - download iPhoto Library Manager and launch.>Click on the Add Library button,
2 - select the library you want to add from those in the selection window.
3 - make sure that in the rebuild window the checkbox "Scavange orphaned photos" is checked.
4 - now that the library is listed in the left hand pane of iPLM, click on your library and go to the Library ➙ Rebuild Library menu option
5 - in the next window name the new library and select the location you want it to be placed. Click on the Create button.
Note 1: This creates a new library based on the LIbraryData.xml file in the library and will recover Events, Albums, keywords, titles and comments. However, books, calendars, cards and slideshows will be lost.
Note 2: Your current library will be left untouched for further attempts at a fix if so desired.
If the iPLM rebuild doesn't work what is left now is to move the Masters folder to the desktop, create a new library and import the image files from that Old Masters folder. You'll have to separate them after import into the groupings that suit you meeds.