Category Archive TEKYHOST BLOG


E-Mail Security

ZIMBRAMAILBOX provides multi layered spam protection system which consists of Cloud Based Spam and Malware gateway and Local Zimbra based Malware scanning services. We provide all this services FREE of charge to our subscribers.

Secure Zimbra Mailbox hosting


E-mail is one of the most widely and commonly used Internet services. The e-mail infrastructure employed on the Internet is primarily made up of e-mail servers using the Simple Mail Transfer Protocol (SMTP) to accept messages from clients, transport those messages to other servers, and deposit messages into a user’s server-based inbox. In addition to e-mail servers, the infrastructure includes e-mail clients. Clients retrieve e-mail from their server-based inboxes using the Post Office Protocol, version 3 (POP3) or Internet Message Access Protocol (IMAP). Clients communicate with e-mail servers using SMTP

E-mail is the most common delivery mechanism for viruses, worms, Trojan horses, documents with destructive macros, and other malicious code. The proliferation of support for various scripting languages, auto-download capabilities, and auto-execute features has transformed hyperlinks within the content of e-mail and attachments into a serious threat to every system.

The first step in deploying e-mail security is to recognize the vulnerabilities specific to e-mail. The protocols used to support e-mail do not employ encryption. Thus, all messages are transmitted in the form in which they are submitted to the e-mail server, which is often plain text. This makes interception and eavesdropping an easy task. However, the lack of native encryption is one of the least important security issues related to e-mail.

E-mail offers little in the way of source verification. Spoofing the source address of e-mail is a simple process for even the novice hacker. E-mail headers can be modified at their source or at any point during transit. Furthermore, it is also possible to deliver e-mail directly to a user’s inbox on an e-mail server by directly connecting to the e-mail server’s SMTP port. And speaking of in-transit modification, there are no native integrity checks to ensure that a message was not altered between its source and destination.

E-mail itself can be used as an attack mechanism. When sufficient numbers of messages are directed to a single user’s inbox or through a specific STMP server, a denial of service (DoS) can result. This attack is often called mailbombing and is simply a DoS performed by inundating a system with messages. The DoS can be the result of storage capacity consumption or processing capability utilization. Either way the result is the same: legitimate messages cannot be delivered. Like e-mail flooding and malicious code attachments, unwanted e-mail can be considered an attack. Sending unwanted, inappropriate, or irrelevant messages is called spamming. Spamming is often little more than a nuisance, but it does waste system resources both locally and over the Internet. It is often difficult to stop spam because the source of the messages is usually spoofed.


Email Viruses and Malware

At ZIMBRAMAILBOX we are doing our best to protect you from Malware and Viruses that are finding there way to mailboxes all over the world. However without our users doing due diligence all this efforts will go unanswered and there is possibility of mailboxes being hacked or compromised

Understanding threats and being able to at very l;east follow best practices is extremely important to keep your Mailbox safe and secured.

Viruses and Malware

When using ZIMBRAMAILBOX all your email is being scanned by our Virus and Spam gateways. However, this scanners cannot prevent all malicious email, and some malicious threats come from the internet.

Types of threats

  • Worms
  • Phishing
  • Trojan horses
  • Viruses
  • Spyware
  • Ransomware

Besides using unique, strong passwords here are some of the most important things you can do to protect yourself from malicious email.

  • Always keep your computer’s anti-virus software and browser software up-to-date
  • Do not Open an email from an unknown address
  • Do not Click a link in an email unless you expected someone to send it.
  • Do not Open an attachment unless you were expecting it or it was from an unquestionably trusted source.

We can not stress this enough how important it is to follow this very basic rules. Being alert and following best practices could make a huge difference. Malware prays on weak users who do not pay attention to details.

Here are some examples of malicious emails that you most likely will encounter when using your mailbox:

1. Spoofs: Spoofing is very easy to do. Example of spoofing would be your receiving email from one of your friends or colleges but it is not actually coming from them. In most cases attacker would spoof from field so email appears like its coming from trusted source.

2. Hacks: An example of a hack would be when one of users in your address book gets hacked and you receive emails from him/her for donation or something very similar.

Other best practices

  • Be careful and selective about what you download to your computer from the internet.
  • Read licensing agreements carefully.
  • Do not click on internet ads.
  • Do not open or accept suspicious error messages in your browser.
  • Do not click on IM links from users you do not know or if they are otherwise suspicious.

Doing any of the above actions can result in software downloads to your computer, and these downloads are often malicious


ZIMBRA vs Office 365

Zimbra is directly competing with office 365 for share of enterprise email market. A lot of our clients ask us. Why choose Zimbra over Office 365?
Lets see why we as consultants we always suggest Zimbra over Office 365 for any business with more then 10 mailboxes.

Zimbra hands down wins the competition when it comes to pricing. Be it Network on Perm. deployment or hosted solution. There is huge difference in pricing and Zimbra is clear winner. On top of this Zimbra provides Free Open Source Edition that is available as evaluation software. In Office 365, there isn’t a provision of any “free account” and users need to pay a minimum monthly subscription.
Office 365 includes the Microsoft suite of Office applications. Zimbra, in addition to email and calendar also offers a host of features such as file sharing, document management, simplified admin controls and an award-winning, AJAX based user interface. On top of that, Zimbra also offers useful features such as cross platform sync, platform search and email sorting, that Office 365 doesn’t. There is also 3rd party plugins that Zimbra fully supports but they are not available for Office 365
Zimbra is an open source software that means organizations can have more control over email operations as there is always a possibility to customize code to suit diverse business requirements. Office 365, on the other hand is a closed source software as only Microsoft is permitted to perform any changes to the code as and when required.
Platform or Device Support
Zimbra supports android, iOS and all leading web platforms. Office 365 also supports android, iOS and some web platforms but lucking supports for some web browsers.

Compare Features

Feature Comparison Guide Zimbra Office 365
Spell Check Y N
Custom dictionary Y N
Page navigation Y N
Print preview Y N
Many signatures Y N
Attachments in reply Y N
Address context in email Y N
Zip file of messages Y N
Appointment created from email Y N
Many message forward Y N
Email as attachment Y N
Contact CSV import / export Y Import Only
Copy and move contacts Y N
Time zone auto mods Y N
Declined appointments greyed out Y N
Small calendar view Y N
Date hover in small calendar view shows schedule Y N
iCal import Y N
Show calendar in iCal format Y N
Continuous, robust and fast search Y N
Searches saved Y N
Sharing contacts with internal, external and public users Y N
Sharing tasks with internal, external and public users Y N
Apps Y Office Only
Inbox size Configurable 25G
Attachment size Configurable 25M
Cross platform compatibility Y N

Why is Zimbra better than Microsoft, Google

  • Lowest TCO in the industry
  • Secure, Private and Compliant by design
  • Access on any device, anywhere
  • Worldwide leader of open source email
  • Extensible through Zimlets, Rest API and more
  • Scales from 10 users to 40M users
  • Run on-prem or in a public or private cloud
  • Worldwide Partner Network to help you where you live and work
  • Why Choose Zimbra Network Edition

  • Now includes Zimbra Drive and Zimbra Chat!
  • Secure & Extensible (augmented with third-party security applications)
  • Private (deployable in-country through ecosystem of hosting partners)
  • Email and phone support plus 24/7 emergency service
  • Real-time synchronization with ActiveSync
  • Real-time backup and restore
  • Advanced search and file indexing for large inboxes
  • Built-in archiving and email compliance
  • Advanced store management and HSM
  • Web client rebranding
  • Multi-tenancy
  • Runs on Mac, Windows & Linux
  • At TEKYHOST we provide professional Zimbra Hosting and Consulting services.


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