Latest pre-release of 10.11.4 breaks Sophos AV Home Edition

I am also having the exact same problem. After updating from OS X 10.11.4 Beta 3 to beta 4 on-access protection is off and can not be enabled.

Note that if you turn System Integrity Protection off, you can enable On-Access Protection and it should stay enabled, at least until the next Beta is released.

Unfortunately that is not working for me. Did send Feedback to Apple earlier. Hopefully others here did so as well.

JohnGillett said:

Unfortunately that is not working for me

Assuming you mean getting On-Access Scanning working, did you turn off System Integrity Protection using csrutil in Terminal while in Recovery?

No, I am unaware of that method. Turned it off in Sys Prefs. What is the command line, please?

JohnGillett said:

No, I am unaware of that method. Turned it off in Sys Prefs. What is the command line, please?

Reboot into Recovery (Cmd+R at the chime). In Utilities>Terminal enter "csrutil disable" and reboot. That will disable SIP and On-Access Scanning should work. Note that this is not a "solution" since Apple added SIP to El Capitan for security purposes and really should be enabled. Moreover, it's likely that any future beta will turn it back on by default. Also, csrutil has three arguments: disable, enable, and status. The first two will only work in Recovery. Status will also work in Terminal after booting normally.

SIP is not new in OS X 10.11.4 Beta 4, it has been there, and enabled, since OS X 10.11 (El Capitan) came out and Sophos on-access protection has been working fine with SIP enabled.

I also reported the issue to Apple.

Thanks very much for the command (and your patience). Now have my Automatic Virus Protection on again.

Did turning off SIP fix the on-access protection for you?

Yes, as mentioned (AVP).

Yes, as mentioned (AVP).