php - Error: Class not found in include_once() in Drupal 7

In doing a module upgrade, I had set the minimum PHP version too high, so when the hook_update functions ran, I got the following error.

Drush command terminated abnormally due to an unrecoverable error.                               [error]
Finished performing updates.                                                                     [ok]
Common requires at least PHP 7.4.32. (Currently using PHP 7.4.3)                                 [warning]

Running the drush cc all command failed, due to numerous missing class files that were confirmed as existing.

Following some advice to rebuild the registry also failed.

Solution:

I verified in the registry table that the class entries were missing. I manually updated the registry from a backup, and things partially worked. Drush was working, then failed totally after clearing the cache.

What I discovered, after looking in the 'system' table was that drush disabled the module that had the PHP version requirement, but left all the other dependent modules enabled. The error message did not indicate that it had done this.

I went to the 'system' table in the database, found the record for that module, and changed the status from 0 to 1. I was able to run drush without issues and successfully rebuilt the cache with

drush cc all

Simple fix, but a frustrating process to discover the problem.