Columbia's Central E-mail System Now Accepts Zip Files

Incoming e-mail zip file attachments are once again permitted for the first time in almost two years. Zip files contain other files that have been compressed to reduce their size, making it easier and faster to e-mail them or transfer them to another medium.

A temporary ban on all incoming University e-mail with zip file attachments was established in 2005 to address the growing problem of embedded viruses in zip files and the inability of antivirus software filters to reject such viruses. The ban did not affect intra-campus or outgoing e-mail with zip files, which have always been allowed. For outgoing mail, the e-mail system receiving the mail could, like ours, make the call to accept zip files or not.

Since the rate of e-mail viruses has dropped considerably in the past few months, we reviewed the zip file policy and created a new rule in our anti-spam filtering software to determine the presence of zip file attachments. Zip files are now tested for viruses in the same way as non-zipped files, such as PDF files, spreadsheets, and images.

Note that some file types, such as executable files, will automatically start running when you click on them. As recommended by Microsoft, CUIT blocks these files in e-mail attachments. To see which file types are still blocked, see About Spam and Virus Filtering.

"Zipping" your files is convenient if you have many files to send or transport, since all of the files are contained within one single "archive" file, with their directory structure retained. Zipping also reduces the size of your files, saving transmission time and disk space.

To store, open or create zip files you will need a compression utility such as WinZip. WinZip includes a Wizard, which guides you through the installation process. Once you have downloaded and installed WinZip, the Wizard will guide you in opening and "unzipping" your file. To create a zip file, click on the Wizard button in the tool bar and follow the instructions.