Method of managing attached document

A method for managing e-mail attachment files received via a network e-mail system by a user. A first e-mail is received at a client computer which includes a first attachment file from the network e-mail system. The client computer begins searching for a second attachment file included with a second e-mail file, preferably automatically after opening the first e-mail. The files are compared to determine if the first attachment file is another incidence of the second attachment file. If true, the method replaces the first attachment file with an identification which points to the second attachment file. When deleting the second e-mail file, the method searches for a third e-mail file. If the third e-mail file is found and the third e-mail file is the next earliest dated incidence of the second e-mail file, the method provides moving and attaching the second attachment file to the third e-mail file.