Is Proofpoint commonly used for corporate email, and how does it affect webmail deliverability issues like blacklisting?

Email marketer from EmailVendorSelection.com explains that Proofpoint's filtering can sometimes be bypassed with sophisticated spoofing or if the email originates from a trusted source. Also, internal email can be blocked by ProofPoint, there can be some configuration challenges, and also false positives can happen.

Email marketer from Slashdot explains that depending on how it's configured, Proofpoint uses sender reputation, content analysis, and behavioral analysis to identify and block spam. Misconfiguration or overly aggressive settings can lead to legitimate emails being blocked.

Email marketer from SuperUser mentions that some Proofpoint appliances might have very aggressive spam thresholds. If the receiving server uses a threshold-based system, your emails might be blocked automatically, despite not being actual spam.

Email marketer from StackExchange responds that Proofpoint acts as a gateway, inspecting email content for malicious links and attachments. If an email is blocked, it may be due to exceeding spam thresholds, containing suspicious content, or originating from a blacklisted IP address.

Email marketer from Spiceworks notes that Proofpoint is used to filter email and protect against threats and depending on its configuration, it can block or quarantine emails deemed suspicious based on various factors like sender reputation or content.

Email marketer from Quora explains that Proofpoint is a common solution for larger companies to filter email before it gets to Microsoft or Google. They provide a layer of spam filtering and analysis that GSuite and O365 do not natively have.

Email marketer from Mxtoolbox describes that Proofpoint blacklists can impact deliverability to many organizations. You can check your IP address against their blacklist using tools like MXToolbox to identify if you're listed and take steps to delist.

Email marketer from Reddit shares that Proofpoint is frequently used by larger organizations for email security. If your IP or domain gets blacklisted by Proofpoint, it can significantly impact deliverability to those organizations, leading to bounces or emails landing in the junk folder.

Email marketer from EmailGeek notes that email deliverability issues related to Proofpoint often stem from being on a blacklist they maintain. If your domain or IP is listed, it can result in emails being blocked or sent to the junk folder for recipients using Proofpoint's services.

Marketer from Email Geeks confirms that Proofpoint is typically used for corporate email. They also suggest setting the rDNS to differentiate from other Sendgrid IPs and mentions this IP should be unblocked from the PP list now.

Expert from Spamresource details that commercial blocklists like the ones used by Proofpoint do have an effect on email deliverability, but they are not used as widely as public blocklists. Being listed on such a list can definitely impact whether your email reaches the inbox of corporate users.

Expert from Word to the Wise explains that Proofpoint is indeed frequently used by larger corporations and that if your email practices trigger their filters, it can cause deliverability problems, including blacklisting. She also mentions that they are fairly transparent with their processes which is good.

Documentation from Proofpoint states their solutions provide comprehensive email security, protecting against malware, phishing, and other email-borne threats. They offer advanced threat detection and prevention capabilities that can filter out malicious content before it reaches the user's inbox.

Documentation from Cisco describes their email security appliance which is a competing product and explains that poor sender reputation, high spam scores, and content matching known phishing patterns can lead to emails being blocked. If Proofpoint or similar services are configured with aggressive settings, legitimate emails might be flagged incorrectly.

Documentation from Spamhaus discusses IP and domain reputation. Poor reputation due to spam activity can lead to blacklisting, and many email security services, including Proofpoint, use such lists to filter incoming emails.

Documentation from Barracuda (a competing email security vendor) explains that services like Proofpoint can cause deliverability issues if your domain or IP is blacklisted. Being proactive about monitoring your sender reputation and implementing best practices for email authentication is crucial.

Documentation from Microsoft Learn explains that Proofpoint can be used to enhance Exchange Online Protection (EOP) by providing an additional layer of security. Proofpoint sits in front of EOP to provide protection before the messages even reach Microsoft's filtering systems.