How can I rebuild my Organizer catalog in Premiere Elements?

Question

The Organizer keeps a catalog of all the media files on your system. In most cases, it will update automatically.
You can also manually update its files by locating the files with broken links (They'll be displaying a "refresh" symbol, red and green arrows in a circle). To update or remove these links, open the full-feature Organizer in Premiere Elements by clicking on the Tagging button under the Organize tab. Then locate the broken link icons, right-click on each and choose the option to update (You'll then be prompted to browse to the file's location) or delete the thumbnail.
As a last resort, you can simply remove the current catalog, forcing Premiere Elements and Photoshop Elements to rebuild it.
To do this, go to C:\Documents and Settings\All Users\Application Data\Adobe\Photoshop Elements\Catalogs\ (In Vista go to C:\ProgramData\Adobe\Photoshop Elements\Catalogs\)and change the name of the folder "My Catalog" to "Old catalog". When you relaunch the program(s), they will recreate the catalog based on the media it locates on your drive(s).

Answer 1

Are you manually copying the .lrcat file from one place to another or are you relying on LR’s backup function to do this?  I would do it manually just to be sure what you’re doing and check the timestamp and size of the copied file and make sure it is the same as the catalog you just copied from.
Also, how are you copying the file from your house to your friend’s house?  Are your computers networked together, somehow, or are you using a thumbdrive/flashdrive, or is the catalog stored on an external USB drive that you copy across? 
How are you opening the catalog at your friend’s house, by double-clicking on it, or are you just starting LR and expecting it to remember what catalog to open?
Are these catalogs on the same drive letter at your friends house, either C: or another drive that you’ve configured to be the same drive letter?
To perfect your process, I’d use a catalog with just one photo in it that you adjust each time in some way that is obvious, and see if you can get that to work and once you are confident with that small catalog, do the large one.
A final point of clarification, by LR catalog you are referring to a single large file name yourcatalogname.lrcat, right, and that file is not located in a Backups folder?  You can check the locaton of your catalog file by using LR / Preferences / Catalog Settings / General tab and the first line in the Information section shows the folder where your catalog resides.