Problem
The following error appears when you click Test Connection at Configuration () > System Settings > Database Backups:
(S)FTP: Unable to open for writing
Cause
This error indicates that WHMCS cannot open a test file in the PHP system directory (the sys_temp_dir PHP setting) via the PHP fopen function.
Solution
Make certain that:
- The
php.inifile includes a validsys_temp_dirvalue. - The PHP system temporary directory has writeable permissions.
- The
fopenfunction is not disabled in the PHP configuration.
Last modified: 2025 July 28