Run Job Error

Good Afternoon
Today I run my backup job but this message appears:

The HTTP response test get a error “Impossível abrir handle de fopen() para http://WEBSITE/?backwpup_run=test&_nonce=74aa7d9b7f”The HTTP response test get a false http status ()

I try to uninstall and install again the plugin but the problem persists.
Thanks for your help 🙂

http://ww.wp.xz.cn/extend/plugins/backwpup/