page not found after migrating drupal 7 to dev version same server using drush archive-restore
A couple of questions:


Are you creating that dev site as a root subfolder of the production site?
If yes, do you get a page not found on the production site OR on the server?


This might be an issue with .htaccess; if you just added dev site to the root of your production website, you might need to add a rule to exclude "/dev".

I think adding this before rewrite conditions for the production site would work:

RewriteRule ^(dev).* - [NC,L]