An Apply update dry-run detected x permission issues error, where x is the number of files and directories that the update process could not overwrite, may occur in the Auto Update window in WHMCS:

The Automatic Updater utility downloads, extracts, and copies the new files during an upgrade, overwriting the existing files.

It performs a dry run test (a test that mitigates the effects of a possible failure) to check the file permissions of all existing files before attempting the overwrite operation. This simulates overwriting the file without making any file changes.

If the dry run encounters a permission problem that could cause the update process to fail, the update process stops before making any changes. The error message lists the full path to each file that has permission issues.

For example:

• /var/www/html/whmcs/configuration.php.new 
• /var/www/html/whmcs/vendor/whmcs/whmcs-foundation/lib/Module

To resolve this error, update the permissions and ownership of the listed files and directories to allow PHP scripts on your server configuration to write to them. After you have updated the permissions and ownership, you can start the update process again at Utilities > Update WHMCS.

For more information on doing this in the cPanel & WHM or Plesk control panels, see:

• How to Assign Permissions to Files and Folders in cPanel
• Changing File and Directory Access Permissions in Plesk File Manager.

For more information about troubleshooting update issues, see:

• Automatic Update Failed: Identifying the problem
• Automatic Updater Troubleshooting