Download iPhoto Library Manager and use its rebuild function. This will create a new library based on data in the albumdata.xml file. Not everything will be brought over - no slideshows, books or calendars, for instance - but it should get all your albums and keywords back.
Because this process creates an entirely new library and leaves your old one untouched, it is non-destructive, and if you're not happy with the results you can simply return to your old one.
Thank you. I have also downloaded This program.
"The album data for this library could not be found.
Opening this library in iPhoto will cause the album data file willl cause the album data file to be created"
I don't know where to go from here.