There may have been a problem with your network configuration, specifically your proxy's hostname. If you have been accessing the Internet with no problems recently, this is unlikely.
Seans go raibh fadhb le cumraíocht do líonra, go sonrach le hóstainm do sheachfhreastalaí. Ach ní dócha é seo má bhí rochtain ar an Idirlíon agat le déanaí.