Update: 5/6: While the reports have decreased, this is still unresolved. Some of the listed providers still have blocks on much less IPs. However, complete resolution is still being pursued.
Original Incident
Currently, we are facing issues where some of our IP addresses have been blocked by Spamcop, ATT, Hotmail, SBC Global, MSN and Microsoft. We are actively addressing the situation and working towards a resolution. If you receive a rejection that relates to the listed services, you may get emails through by sending email from Firespring webmail, https://email.firespring.com