Site down after restoring to backup

I had a sticky problem caused by enabling pretty urls which stopped me from logging in. I decided just to restore the site to a previous backup version through my web host’s dashboard (Dreamhost). After the restore (and all subsequent attempts to restore), the site is completely broken. At first it was a generic HTTP 500 error, and now it’s a PHP error. Dreamhost tech support can’t explain why restoring the site to a previously working version seems to have crashed the site instead. Any ideas?? Should I completely re-install Concrete (assuming I can do that without losing my site content)? …or maybe there’s a simple fix? Here’s the PHP error I’m getting (site is weightofempathy.com):

Fatal error : Uncaught Error: Class ‘\Concrete\Core\Backup\ContentImporter\ContentImporterServiceProvider’ not found in /home/macroverse/weightofempathy.com/concrete/src/Foundation/Service/ProviderList.php:37 Stack trace: #0 /home/macroverse/weightofempathy.com/concrete/src/Foundation/Service/ProviderList.php(25): Concrete\Core\Foundation\Service\ProviderList->createInstance(’\Concrete\Core\…’) #1 /home/macroverse/weightofempathy.com/concrete/src/Foundation/Service/ProviderList.php(48): Concrete\Core\Foundation\Service\ProviderList->registerProvider(’\Concrete\Core\…’) #2 /home/macroverse/weightofempathy.com/concrete/src/Foundation/Runtime/Boot/DefaultBooter.php(320): Concrete\Core\Foundation\Service\ProviderList->registerProviders(Array) #3 /home/macroverse/weightofempathy.com/concrete/src/Foundation/Runtime/Boot/DefaultBooter.php(104): Concrete\Core\Foundation\Runtime\Boot\DefaultBooter->initializeServiceProviders(Object(Concrete\Core\Application\Application), Object(Concrete\Core\Config\Repository\Repository)) in /home/macroverse/weightofempathy.com/concrete/src/Foundation/Service/ProviderList.php on line 37

Pretty URLs adds an invisible .htaccess in the iste root. Associated with it, canonical urls could be enabled by data in /application/config.

Also beneath application/config is a flag to put the doctrine database entities into development mode and a flag to enable pretty urls.

If your restore was database only, the above changes to files may need to be reverted manually.

I believe all the files are restored to their previous state. Restoring the database is a separate process I believe. Maybe they both need to be restored simultaneously to identically-dated backups??

Yes. Though if no files have been removed, you can work with a database that predates the files and adjust the configuration data in application/config by hand.

The database is the critical part of reverting a site.