Thanks, Rich.
I checked the settings in Admin/ Site Settings, Host/ Hosting Settings, on individual pages, and on individual modules, and they are all set to be MinimalExtropy, use portal default, or use page default.

Thanks for pointing out the permissions issue with the Photo Gallery page, but when I click on the edit button it doesn't actually let me edit anything, and when I checked the page permissions, All Users can only View the page ... weird.

Also, please let me know where you saw modules that did not have the error message. I can't see them.

Finally, I logged in as both admin and host and still can't see a link to upload a new skin.

Is there a way to manually get into the database and force a reset of all pages to use the default skin? Is that the best option?

All of this upgrading originally started because the site was "hacked" twice so that it only displayed a "you've been hacked" message.  Both times the web hosting service restored a backup to get back to the correct state.  Do you think the hacks could still be affecting the site now?

Hi Richard,

You have the skin container on your computer but not on the server? Did you try to re-install/repair the skin by uploading it again. Try to re-install through the Host/Extensions menu. If the site was hacked it may well still be compromised. You said that the web host restored from a backup. Was the container displaying properly after the restore? If the problem only occurred after the upgrade to 5.6.2 then it may be that the container/skin is not compatible. Check with XD Design if it is. If it's not there should be a patch available or they can advise you. I don't know a way to specify in the DB how to change a container for an instance on a page. If you cannot access or upload skins via the Host/extension page there may be other issues with your install. As a last resort you could try to manually upload the container files via FTP. If the skin was initially installed at the host level you will find a skin specific folder under yoursite.com/Portals/_default/Containers/NameofYourSkin. If it was installed at the site level look for the container folder in the corresponding portal id folder. If you find the YourSkinName container folder, compare it to the folder on your PC and upload any missing files.

Let me know how you make out.

Rich