Hello, After 2 days of trying to upgrade my Mid-2011 13" MacBook Air from Yosemite to El Capitan, I finally managed to have it up and running (after over 10 re-installations/system restore/clean install tries). So I have a Dell UltraSharp U2413 attached as an additional external monitor, and after each OS upgrade, I have to re-force RGB mode to enable the picture quality to be clear. However, I found out with El Capitan's SIP feature, I have to enable rootless, as per instructions here: http://www.ireckon.net/2013/03/forc...ix-the-picture-quality-of-an-external-monitor However, the csrutil command appears to be missing from my system. I took a screen shot, and attached here. Background: 1. For my first upgrade/installation attempt of El Capitan, I rebooted into Recovery Mode after the complete install, to disable csrutil. That function appeared then. Subsequent attempts to reinstall El Capitan, csrutil command seemed to have disappeared. 2. My most recent successful (12th attempt) installation of El Capitan, I resorted to this thread and followed his advice to move 3rd party kexts to another folder: https://forums.developer.apple.com/message/67556 So, is there another way to disable SIP? Or how do I go about to re-instating the csrutil command? Thanks!