Problem #

The following error appears when you click Test Connection at Configuration () > System Settings > Database Backups:

(S)FTP: Unable to write to temp file

Cause #

This error indicates that WHMCS cannot write to a test file in the PHP system directory (the sys_temp_dir PHP setting) via the PHP fwrite function.

Solution #

Make certain that:

• The PHP system temporary directory has writeable permissions.
• The fwrite function is not disabled in the PHP configuration.

Last modified: 2025 July 28