ITS Documentation

Install Sophos Anti-Virus for Mac OS X

S4366 • June 2015

ITS strongly recommends that you protect yourself from malware by installing the U-M-licensed Sophos Anti-Virus. Sophos Anti-Virus protects against viruses, worms, and other malicious attacks. This document provides instructions for installing Sophos Anti-Virus on university-owned, non-MiWorkspace computers. A home version is available for your own devices. See the Safe Computing Anti-Virus page for details.

Table of Contents

Who Can Install

Sophos Anti-Virus is available to all University of Michigan faculty and staff for use on university-owned, non-MiWorkspace computers only. (MiWorkspace machines include anti-virus protection with automatic updates.) Students, faculty and staff seeking anti-virus software for their personally-owned Apple Macintosh computers can download Sophos Anti-Virus Home Edition. To install Sophos Anti-Virus on your personal computer, visit Anti-Virus Protection at U-M on the Safe Computing website.

System Requirements

  • Mac OS 10.6 and up

  • Mac with Intel

  • 450 MB of disk space

  • 450 MB of memory

  • High-speed Internet connection

What Sophos Anti-Virus Does

Virus checks. Sophos automatically checks for viruses whenever you open and close files, start applications, and take other actions on your Mac.

  • If Sophos determines that a file is infected, it will attempt to disinfect the file.

  • If it cannot, Sophos will move the file to a special folder.

Automatic updates. Sophos Anti-Virus keeps itself current by checking hourly for new updates whenever your computer is connected to the Internet. It installs updates as they become available. This happens in the background and does not interfere with your use of your computer.

Before Installing

  1. Uninstall any existing anti-virus software. This includes earlier versions of Sophos Anti-Virus.

    1. If you already have Sophos Anti-Virus installed, but it isn't the newest version, click Update Now from the Sophos menu. Your installation should be updated to the newest version automatically.

    2. If your version of Sophos is not automatically updated, or you would like to upgrade it manually, follow the instructions for uninstalling an older version of Sophos Anti-Virus in Appendix B: How to Uninstall Sophos Anti-Virus. After that, follow the instructions for Installing Sophos Anti-Virus below.

    3. To uninstall another anti-virus software program, check the appropriate vendor's website.

  2. Download Sophos Anti-Virus U-M from the Blue Disc website. Select your Mac operating system, and click Download next to Sophos Anti-Virus U-M.

  3. Disconnect your computer from the Internet for added protection before proceeding with the installation. Disconnecting minimizes your exposure to hostile code.

Installing Sophos Anti-Virus

  1. If the installer did not automatically open after downloading, double-click the Sophos_Anti-Virus_U-M.dmg file. It should be located on your Desktop or in the Downloads folder.

  2. In the Sophos Anti-Virus U-M window, double-click Sophos Anti-Virus.mpkg.

  3. In the Install Sophos Anti-Virus window, click Open.

  4. In the Welcome to the Sophos Anti-Virus Installer window, click Continue.

  5. Follow the on-screen instructions to finish installing the software.

After the installation is complete, you can safely move both the Sophos Anti-Virus U-M installer and the Sophos_Anti-Virus_U-M.dmg files to the Trash.

Keeping Sophos Up-To-Date

Immediately after installation, run Sophos's Update Now to get the most recent version of the Sophos program and its virus definitions. The first time you run it, Update Now may take several minutes, depending on your Internet connection.

  1. If you disconnected your computer from the Internet while installing Sophos, reconnect it now.

  2. If you have a CD or DVD in your CD/DVD drive, eject it now.

  3. Click the Sophos icon in the menu bar, then click Scan This Mac.
    NOTE: If you see Cancel Update instead of Update Now, Sophos is already updating.

AUTO-UPDATING: Restarting your Mac will configure Auto-Update. Whenever your Mac is connected to the Internet, Sophos checks for updates every hour and automatically installs an update when it finds one. It does this in the background, so it doesn't interfere with your work.

U-M Recommended Settings

After updating Sophos Anti-Virus, modify the Sophos Preferences to use U-M recommended settings.

  1. Click the Sophos icon in the menu bar, and select Open Preferences.

  2. Click the padlock to unlock Preferences so you can make changes. Authenticate with your Mac computer password to confirm that you want to make changes.

  3. Adjust the following preferences.

On Access tab

Leave the following settings as they are:

  • On-Access Scanning. If your computer's performance is degraded by On-Access scanning, try disabling this setting.

  • Scanning Inside Archives and Compressed Files.

  • Files on Network Volumes.

Auto Update tab

Make no changes.

Logging tab

Use the following log file path: /Library/Logs/Sophos Anti-Virus.log

Message tab

Enable the following settings:

  • Display a Desktop Alert when a Threat is Detected on Access.

  • Warn before Cleaning Up Threats in Quarantine Manager.

  • Show Sophos Anti-Virus Status in Menu Bar.

Live Protection tab

Enable Live Protection.

Web Protection tab

Enable the following settings:

  • Block Malicious Access to Web Sites in Real Time.

  • Block Malicious Downloads from Web Sites.

Scan Your Computer for Viruses

After installing Sophos Anti-Virus, scan your computer for viruses.


  • If possible, disconnect from any networked drives. Deselect network drives that appear in the list of items to be scanned.

  • Eject all CDs and DVDs.

  • Clear your web browser's cache.

    • Safari users, under the Safari menu, click Empty Cache.

    • Chrome users, from the Chrome menu, select Tools, then Clear browsing data.

  • Empty your Mac's Trash.

This first scan may take several hours, depending on the number of files and applications on your Mac, but you can use your computer while the scan is in progress.

  1. Under the Sophos menu bar, select Open Scans.

  2. Click Scan Now to scan your Mac and any attached hard drives or other writable storage devices, such as a USB flash drive.

    ABOUT ERRORS: Sophos Anti-Virus cannot scan all files. For example, it cannot open private files, and it cannot scan encrypted files. It may report these as errors. You can ignore these error messages.

  3. When the scan is complete, Sophos will report if it found any threats. From the Scan menu, select View Scan Log to see more detail.

  4. If Sophos detects a virus on your computer, choose to quarantine or delete the affected files. If you are unsure what to do, contact the ITS Service Center.

You only need to perform this manual scan once. After that, Sophos will regularly scan your computer and attached hard drives and other media.

Check Periodically to Verify that Sophos is Updating Automatically

If Sophos Anti-Virus is unable to complete a update using either Update Now or its regular hourly update, an X will appear inside the Sophos menu bar icon. If Sophos is not updating automatically, check the following:

  • Check your Internet connection. AutoUpdate can only function when your computer is connected to the Internet.

  • Check your firewall. If your firewall is blocking Port 80, AutoUpdate will not be able to run. You can, however, run Update Now.

  • Check your computer’s clock. If it is not set to the correct time, it could be out of sync with the clock on the Sophos server and Sophos will be unable to update.

  • Restart your computer and run Update Now if Sophos Anti-Virus is still not updating automatically.

Additional Resources

To access the Sophos Anti-Virus built-in Help:

  1. Open Sophos Anti-Virus.

  2. Click the Help menu and enter a search term, or click Sophos Anti-Virus Help for an index.

Visit ITS's Information System to obtain ITS computer documentation and other resources.

The ITS Service Center provides a variety of computing help resources.

For further help with this or any other topic, call 734-764-HELP [4357] or submit an online service request.

Appendix A: Download the U-M Sophos Installer

  1. Visit the Blue Disc web site.

  2. Select your operating system.

  3. If you are prompted to log in on the U-M Weblogin page, enter your uniqname and UMICH password.

  4. Locate Sophos Anti-Virus U-M in the list of software and click Download.

  5. After clicking Download:

    • Click Save if you are prompted to open the file or save it to your computer.

    • Click Continue or Keep if you are notified that the file being downloaded contains an application and asked if you want to continue downloading.

  6. The Sophos_Anti-Virus_U-M.dmg file will download to your Desktop or your Downloads folder.

Appendix B: How to Uninstall Sophos Anti-Virus

NOTE: This will remove Sophos even though the window and final button are named Install.

  1. Open Finder. Click on your hard drive, open the Library folder, then the Sophos Anti-Virus folder.

  2. Double-click Remove Sophos Anti-Virus.pkg

  3. Click Continue when prompted to uninstall the software.

  4. Select your hard drive in the Select a Destination window. Click Continue.

  5. In the Easy Install window, click Install.

  6. Enter your Mac password to confirm the uninstallation.

  7. When the uninstall has successfully completed, you'll receive a confirmation message.

  8. Continue to Installing Sophos Anti-Virus.