Anti spam and anti viruse systems are very important measures for e mail security. Although the author finds it practical to install anti virus software on every personal computer, he also feels that not all users are willing to install such software. It is important to develop an anti spam system and an anti virus system on computers for e mail administration. This papaer describes a method of developing such systems by using open source software. The official documents enabled the successful development of the system. As a result of testing after development, we found that systems are running without any problem.