how to activate SIP?

You have to run the command in the Terminal while in Recovery Mode.

Maybe you have an old recovery volume that does not yet have csrutil. You might backup, then delete the old recovery volume and create a new. I guess using Carbon Copy Cloner is one way to do this but maybe applying the full macOS installer might also do that.

Lance.scs wrote:

SIP has been turned off since Big Sur has been installed.

How do I switch it on?

Using: csrutil enable gives me : Command not found

PLEASE HELP ME OUT

To see your current SIP, from Terminal copy and paste:

csrutil status

Rather than booting into Recovery Mode again, If it is disabled— copy and paste:

csrutil clear

Reboot if necessary, check your status—post back your success or failure here.

Lance.scs wrote:

SIP has been turned off since Big Sur has been installed.

Thank you Leroydouglas, I tried but as before: command not found

Which command is not found, there are two posted ?

csrutil status

Are you admin?

Is this your personal machine or is the device bound to Enterprise, JAMF, MDM, active directory list (?)

From >System Preferences>Security & Privacy what happens if you add Terminal.app to the Full Disk Access folder, does this make a difference ?

Do you happen to have third party "TotalFinder.app" installed on this machine?

What is your SIP status if you relaunch Finder from the >Force Quit> Finder Relaunch

and test your status ?

Lance.scs wrote:

But the common does not exist.

It does on my 5 Macs running Big Sur.

Is there any other way to enable SIP?

Not that I'm aware of.

Thanks,

Andre

You're welcome.