Even thought that the employer might not explicitly state in any company policies that the electronic mail system can be used for private message exchange. Employees are expecting that their e-mail accounts are private in the fact of accessing their accounts is restricted by the use of personal passwords. As such, employees believe that they should have an absolute right to privacy for their e-mail communication. Also, most of the companies' electronic mail system has the connection to the Internet. The ability to communicate with the outside world makes the employees believe that the e-mail system is not strictly restricted to business related use.
Employees tend to use the system to send e-mail to friends and colleagues naturally.
Furthermore, the misunderstanding or the lack of clarification of the company's policy, and the lack of knowledge on electronic communication and computer networks, employees have forgotten some important facts when using the e-mail system. When electronic mail system is used at a company, the employer owns it and is allowed to review its contents. Messages sent within the company and as well as those that are sent from your terminal to another company or from another company to you can be subjected to monitoring by your employer. Most of the electronic systems retain messages in memory even after they have been deleted. Although it appears they are erased from the employee's terminal, they are often backed up by someone or an automatic system in the IS department along with other important data from the computer system to prevent data lost or power failure.