TC Features – Email Security

Subscribers have access to a broad range of email defenses, which can be blended to provide exceptional inbox control. Default and custom configurations simplify deployment, while providing the versatility needed to address the widest range of user requirements.

SMTP Enforcement

TC leverages its LDAP sync capabilities to maintain a database of known users at each customer domain. This database enables the system to deny delivery of mail to unknown users after receiving the “To:” address from the message envelope. This approach provides protection against directory-harvest and denial-of-service attacks (DHA and DoS, respectively), and saves considerable bandwidth.

Recipient Checking

In cases where TC has not been provided with a list of users for an enterprise, the system automatically queries the customer’s MTA to determine if a recipient is legitimate.

Allow Lists (Whitelisting)

Users can get started by using TC Outlook Contact Harvester to build a list of their email correspondents. This utility collects Outlook contacts and addresses from messages in the Sent Items folder. Automated “allow list on first outbound” and “allow list on reply” features keep one’s allow list current over time. Allow lists can include individual addresses or entire domains, and support enterprise-wide entries.

Block Lists (Blacklisting)

The block list is used to block email from specific addresses or domains. A block list entry can be created through either the in-message user control panel or the TC's Message Center user interface. Enterprise-wide entries may be added to the block list.

Content Filtering

TC leverages content filtering to screen messages from senders who are not on a recipient’s allow list yet have previously passed prior tests, such as permitted countries and permitted languages. Filtering provides simple, transparent set-and-forget protection, although a user may choose to inspect their quarantine or receive a daily summary of messages in the quarantine. TC provides other simple settings to further adjust filtering sensitivity for highly specific preferences.

Address-on-the-Fly™ (AOTF)

TC's Address-on-the-Fly enables users to spontaneously disclose a purpose-specific address on a website, in a discussion forum, in print or conversation without interacting with the system. These addresses take the form of a root name plus a suffix of the user’s own choosing. For example, to register on eBay, Jane Doe might disclose the address, where the “.ebay” suffix serves as an “email PIN” that assures delivery of email sent to this address. Addresses are independently controllable by policy so that legitimate users of the address can be “locked down” in the event the address is ever harvested and abused by a spammer.

If an Address-on-the-Fly starts to attract spam, the user can first identify who is sharing the email address and then exert varying degrees of control over future use of the address. The user can (a) block the specific abusing sender, (b) lock down the address, reserving its future use solely for the existing community of legitimate senders, (c) restrict future use to senders at the domain of the sender to which it was initially disclosed, (d) restrict use even further to just the party to which it was initially disclosed, or (e) disable the address, in which case all future incoming mail on the address will be blocked, flagged or challenged. These options are implemented very simply through the optional user control panel present in the bottom of email messages. Learn more here about Address-on-the-Fly

User Control Panel

As an option, TC automatically inserts a control panel at the bottom of incoming messages, and removes it on Forward or Reply. This control panel provides a means of communicating with users, for example, to inform them when one correspondent appears to have shared their address with a third party. It also provides a simple means for users to update their access preferences for a specific sender and address simply by clicking on the intuitive in-message links that are provided. TC's control panel is available in English, Spanish, French, German, Brazilian Portuguese, Dutch, Italian and Chinese, with Russian and Hebrew on the way.

TC Permitted Languages

This capability augments traditional content filtering by blocking messages in any language other than those specifically approved for delivery at the enterprise and individual user levels.

TC Permitted Countries

This capability further augments content filtering by blocking messages from any country other than those specifically approved for delivery at the enterprise and individual user levels. Delivery decisions are based on the IP address of the sending server. While some organizations with international clients may not use this capability, many domestic businesses may not ever want to receive email that can be determined to have originated outside their home countries or geographic areas of operation.


TC scans both incoming and outgoing email for viruses, worms, and other malware.

Blended Defenses

TC enables users to mix and match various defenses to suit their specific preferences. Our experience shows that blending Protective Addresses with traditional methods produces a stronger defense that also avoids the pitfalls of traditional defenses used independently.