CQ5.2.X to CQ5.3 Upgrade: Custom 5.2 Resource Resolver configuration causes 5.3 to return 404s for all pages

Issue

After upgrading from CQ5.2.X to CQ5.3 we get 404 Not Found responses are returned for all pages.
or
After installing our CQ5.2.X application code package to a CQ5.3 instance 404 Not Found responses are returned for all pages.

Cause

If you have defined a custom OSGi configuration for JcrResourceResolver in CQ5.2.1 under /apps/<appname>/config/org.apache.sling.jcr.resource.internal.JcrResourceResolverFactoryImpl then if you install this same configuration in your 5.3 instance then it will cause all of the pages in the 5.3 instance to return 404 statuses.

Resolution

1. Log into http://<host>:<port>/crxde as admin user
2. Browse to /libs/sling/config/org.apache.sling.jcr.resource.internal.JcrResourceResolverFactoryImpl
3. Copy or correct each of the entries from the String[] property resource.resolver.searchpath to the one in your custom configuration under /apps/<appname>/config*/org.apache.sling.jcr.resource.internal.JcrResourceResolverFactoryImpl

Your final org.apache.sling.jcr.resource.internal.JcrResourceResolverFactoryImpl/resource.resolver.searchpath property should have the following values: /apps,/libs,/apps/foundation/components/primary,/libs/foundation/components/primary

Applies to

CQ5.2.X to CQ5.3 Upgrade