Listing in the ivmSIP/24 blacklists indicates that your IP address has been identified as a spam-sending server. Whether or not you operate an email server on this IP address, it has either sent spam or has been previously identified as such.
More information about ivmSIP can be found at their website: https://www.invaluement.com/#sip
Reason for listing -
Email is the key to your customer communication strategy. But, what is your email reputation?
Setting up and managing your DMARC configuration is the key to getting insight into your email delivery. MxToolbox is the key to understanding DMARC.
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