Why am I losing photo descriptions?

Question

I transferred to a brand new MacBook Pro (OS X v. 10.6.8) from my old MacBook last week.  I had begun adding descriptions to a new album on the old computer.  After I transferred, the descriptions I had written were gone.  However, if I edited them with Photoshop Elements, the description would sometimes reappear after the edit.  I re-typed them (over 1000!) on my new mac with iPhoto '11 over the last 3 days and overnight they disappeared.  I have 2100 pics in this album from a long trip and I want to have descriptions on all of them.  I've already spent hours on this and really don't want to start over for a third time.  I am writing the descriptions in the "description" field in "info", not in the title field - which is already difficult because the curser moves out of the field as I'm typing for some reason.  Does anyone know what is going on and how I can recover all of those descriptons?  They must be in there somewhere if Photoshop can see them.

Answer 1

First try the simple fix: 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 the situation Make a temporary, backup copy (if you don't already have a backup copy) of the library 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.
Select the options identified in the screenshot. 
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.
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