Usually this is caused by third party plug-ins, especially those from Topaz. If you've installed anything, check with the developer for updates for lion.
I have nothing from Topaz. When I asked Apple about the problem, they said it was an Adobe problem.
Have you installed any plugins? I didn't mean to check with apple for updates to lion; I meant to check with the makers of any plug-ins you have added to PSE, regardless of whether or not they're from Topaz, to see if they need to be updated for lion.
What is Topaz? Never used it.
Topaz is a very popular maker of plugins for noise reduction, sharpening, artistic effects. Did you delete the preferences for PSE when you installed lion? If not, go to your username>library>preferences and delete:
Adobe Photoshop Elements 9 settings
Adobe Photoshop Elements 9 paths
and any lockfiles with the same names. That library folder is hidden in lion. To see it, in the finder hold down the option key while you click the Go menu. It will appear below the little house for your user account. While you're in there, go to Saved Application States and delete anything relating to PSE. I'd also suggest repairing permissions before restarting PSE.
Thank you for that last set of instructions. I never would have figured that out on my own. It seems to be working now.