Some time ago, I installed Sophos Antivirus on my Macbook Pro running Snow Leopard and came up against the "computer stops responding after reboot, with Sophos Antivirus installed and FileVault enabled" issues. This required me to forcibly power-off the computer by holding down the power button on every restart and having to boot into single user mode to manually remove the application files before I could use the computer again.

Has the situation changed with the latest version of Sophos Antivirus (version 8 at time of writing). Is anyone successfully using it on Lion with (legacy) FileVault enabled? I'd like to try again, but would obviously prefer not to encounter the above problems.

  • Do you have any windows PCs that you frequently share files with? I'm asking because Sophos antivirus (like most mac viruses) primarily work to prevent the accidental infection of windows PCs by macs that share files.
    – Alexander
    Commented Apr 12, 2012 at 15:53
  • @XAleXOwnZX I have both Macs and Windows PC's in my network.
    – binarybob
    Commented Apr 12, 2012 at 18:16

1 Answer 1


You need to increase the number of on-demand scanner threads, to prevent a deadlock when you log in if you have a number of things all trying to start at once.

Run the following, from Terminal:

sudo defaults write /Library/Preferences/com.sophos.sav WorkerThreads -int 20

(20 works for me, with the number of applications that I have set to launch at login time)

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .