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 #

Verify that the following statements are true for the PHP environment where you have WHMCS installed:

• The php.ini file includes a valid sys_temp_dir value.
• The PHP system temporary directory has writeable permissions.
• The fopen function is not disabled in the PHP configuration.

Last modified: 2025 August 15