I had previously updated with this. However, my PC crashed and when I reloaded the PSE9, now it won't let me do the update. Since they no longer offer tech support, they suggested this forum. Is this update really necessary or important? I'm always afraid I will miss something if it doesn't get loaded. I am able to use the program so please advise. Thank you.
The 9.0.3 update was mainly about issues concerning the use of Wacom tablets. If you do not use such a tablet, you don't need this update.
You can also try downloading and installing this update directly: http://helpx.adobe.com/photoshop-elements/kb/troubleshoot-catalog-backup-conversion-elemen ts.html