Right in the middle of the process of creating a hardcover photo book, a message came up, telling me: This theme is no longer available in iPhoto. Please choose: Delete book / Cancel / Change Theme. No matter what I select. What`s the problem???

Question

No matter what option I select- iPhoto either crashes or the beachball starts spinning. Either way, I can`t access the photo book anymore.
Is there anything I can do?
The selected theme is definitely still available in iPhoto, so this can`t be the real problem...
I have been sitting on the book work for days...
Thanks for any help!
Dennis

Answer 1

Make a temporary, backup copy (if you don't already have a backup copy) of the library and try the following:
1 - delete the iPhoto preference file, com.apple.iPhoto.plist, that resides in your
     User/Home()/Library/ Preferences folder.
2 - delete iPhoto's cache file, Cache.db, that is located in your
     User/Home()/Library/Caches/com.apple.iPhoto folder. 
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3 - launch iPhoto and try again.
NOTE: If you're moved your library from its default location in your Home/Pictures folder you will have to point iPhoto to its new location when you next open iPhoto by holding down the Option key when launching iPhoto.  You'll also have to reset the iPhoto's various preferences.
If that doesn't help   launch iPhoto with the Option key held down and create a new, test library.  Import some photos and check to see if the same problem persists. If it does then a reinstall of iPhoto is warrented.
If the problem does not appear in the test library then your current library is damaged.  In that case make a temporary, backup copy (select the library and type Command+D) and  apply the two fixes below in order as needed:
Fix #1
Launch iPhoto with the Command+Option keys held down and rebuild the library.
Since only one option can be run at a time start with Option #1, followed by #3 and then #4.
Fix #2
Using iPhoto Library Manager  to Rebuild Your iPhoto Library
Download iPhoto Library Manager and launch.
Click on the Add Library button, navigate to your Home/Pictures folder and select your iPhoto Library folder.
Now that the library is listed in the left hand pane of iPLM, click on your library and go to the File ➙ Rebuild Library menu option
In the next  window name the new library and select the location you want it to be placed.
Click on the Create button.
Note: This creates a new library based on the LIbraryData.xml file in the library and will recover Events, Albums, keywords, titles and comments but not books, calendars or slideshows. The original library will be left untouched for further attempts at fixing the problem or in case the rebuilt library is not satisfactory.
OT