Purpose
This test determines if your sending IP address is listed on two of Spamhaus' critical blacklists. Email sent from IP addresses listed on these critical blacklists encounter deliverability problems and is usually blocked or placed into the spam folder.

How it works
When a campaign is sent to Inbox Monitor, Inbox Optimizer checks the sending IP address for that campaign each morning at 8:00 am Mountain Time to see if the IP address is listed on either the Spamhaus Policy Block List (PBL) or the Spamhaus Block List (SBL).

This test does not check blacklist status in real-time so a delisted IP address will not show as delisted until 8:00 am Mountain Time the next day. To check if your IP has been delisted in real-time, use the Spamhaus IP lookup feature on the Spamhaus website.

Results

• Pass: If the sending IP address is not listed on the Spamhaus Policy Block List (PBL) or the Spamhaus Block List (SBL)
• Fail: If the sending IP address is listed on the Spamhaus Policy Block List (PBL) or the Spamhaus Block List (SBL)