Live updating blacklist of proxy sites
If you are running anti-virus software on your firewall or SMTP server, check for the setting "Internet Email Auto Protect" or "Internet Email Protection." If this setting is enabled, disable it and try sending a test message to our servers again. If you are unable to connect, then attempt to telnet over port 25 directly to our email servers (MTAs).You can find the current list of our MTAs by querying "nslookup –q=mx hotmail.com" from a command prompt (this should work in a variety of Operating Systems).When selecting a computer system for use as a dedicated Squid caching proxy server for many users ensure it is configured with a large amount of physical memory as Squid maintains an in-memory cache for increased performance. The following examples illustrate some of the directives which may be modified to affect the behavior of the Squid server.For more in-depth configuration of Squid, see the References section.Squid also supports a wide variety of caching protocols, such as Internet Cache Protocol (ICP), the Hyper Text Caching Protocol (HTCP), the Cache Array Routing Protocol (CARP), and the Web Cache Coordination Protocol (WCCP).The Squid proxy cache server is an excellent solution to a variety of proxy and caching server needs, and scales from the branch office to enterprise level networks while providing extensive, granular access control mechanisms, and monitoring of critical parameters via the Simple Network Management Protocol (SNMP).The challenges of network and data security are complex, but solving them does not need to be.Barracuda is your single source for securing all of your threat vectors, including email, websites, web applications, mobile devices, and network performance - whether on-site or in the cloud.
Once the IP has built a reputation for not sending spam, will typically allow for a better email delivery experience.This wiki How will guide you through the various processes of blocking your IP address.It will also help you gain a better understanding of how IP addresses and proxies work.If you are able to connect directly to the IP and not mail.hotmail.com, then it is likely there is an issue with your DNS server.
Occasionally, some of the IPs in our MX record may be out of service.
If you are connecting to one of these IPs your connection may timeout. You may also configure your outbound email server to do a round-robin DNS lookup for