1.7 → 8 or 8 → 9 migration that blew up: modules throwing fatals, blank BO, payments down, SEO in free fall. We audit the current state, quote by order of criticality, recover piece by piece. Without starting from scratch, without breaking it all again.
Across 14 recoveries delivered in 2025-2026, here's the damage we consistently encounter, ranked by business criticality. The more this list rings a bell, the wider the recovery scope.
Not a generic checklist. A real prioritised diagnostic that distinguishes what's losing you revenue today from what can wait.
ps_install and the new Symfony tables in 8.x)?
error_log + php-fpm.log over the last 7 rolling days. PrestaShop debug mode temporarily enabled on 3 key pages (home, product, checkout). List of fatals, deprecated, warnings.
/override/: parent class signature comparison vs current version.
Audit free. For the recovery, you know exactly what it costs before we touch the code.
If you're still on 1.7 and want to move up to 8.x without breaking anything, that's a new migration project: staging tests, upstream module audit, planning. It's not recovery, it's prevention. Request a quote.
If just one 500 error appeared after migration, that's a targeted troubleshoot, not a full recovery. Dedicated page, less expensive.
500 page → ❌ Not just a slower siteIf the migration went fine but the site is just slower than before, that's a performance topic, not a recovery. Dedicated page.
Performance page →Tools::displayPrice() methods removed in 8.x, renamed hooks. Number one cause on 1.7 → 8/9. (2) Overrides in /override/ inheriting from core classes whose signature changed. (3) Custom theme with Smarty variables or hooks removed. Bonus: 70% of post-migration incidents come from an auto-upgrader run without staging.robots.txt hasn't been reset to Disallow: / by default (badly cleaned staging case). (4) Core Web Vitals audit. Return to normal typically within 30-60 days after redirects.Free 45-min post-migration audit: we list the damage, we quote, we prioritise. Quote within 24 business hours.