I am trying to migrate a Drupal 7 site to Drupal 9 using the Migrate module user interface. I have read through and followed the corresponding tutorials on drupal.org, but the migration still fails.
Given that my original Drupal 7 site is quite complex, for testing purposes, I created a fresh installation of Drupal 7 and created some dummy nodes; then I ran the upgrade from the user interface in Drupal 9.
The What will be upgraded? page indicated that 29 modules would be upgraded (including the Node module). After performing the upgrade, I got the following messages:
Completed 39 upgrade tasks successfully
40 upgrades failed
Upgrade process not completed
The content hasn't been migrated.
When I checked the upgrade log, I found the following error:
Migration d7_node:article did not meet the requirements. Missing migrations d7_node_type, d7_user. requirements: d7_node_type. requirements: d7_user.
The d7_node_type.yml and d7_user.yml migration files are there in the appropriate Drupal 9 folders, so I don't understand what the problem is. What am I missing?