Whitelist or blacklist?

[NetGuarana]

Hello,
There is a hosting company in Brazil, called Locaweb, with several email servers and many real clients and accounts. However, this same company commonly allows its numerous customers to send many SPAMs or unwanted messages.
Commonly, the IPs of this company and its email servers are added to blacklists and the biggest problem is that EITHER real emails are not received OR SPAMs are received without any verification.
How should I go about resolving this?

[magicspam]

Hello NetGuarana,

Thank you for your post.

If the company is being used to send a lot of spam from their servers, such companies will eventually be listed on the BMS list available in MagicSpam (and other systems). Once listed their messages will be blocked until the spamming issue is resolved and their IPs are delisted.

In the meantime, we would recommend notifying the company of the compromises and spam and then blacklist their IPs until they resolve the issue, and in the meantime, whitelist their good senders based on the original email address.

Additionally, you can reach out to our MagicSpam support team via: support@magicspam.com and provide them more information on this particular spam, after which our Spam Auditor team can devise a new set of rules to filter those spam messages.

We hope this information helps.

[annathree]

Notify Locaweb about the spam issue from their servers.
Blacklist spamming IPs while awaiting Locaweb's action.
Whitelist legitimate senders to ensure important emails aren't blocked.
Contact MagicSpam support at support@magicspam.com for assistance.
Follow up with Locaweb for resolution and ongoing monitoring.