We recommend that you remove any third-party drivers from your system before upgrading to the current release of SCO OpenServer, then restore the drivers after you have rebooted successfully following the upgrade. This is the safest approach because, if a third-party driver from your previous SCO OpenServer system is not compatible with the current release of SCO OpenServer, the kernel (/stand/unix) might not link at the end of installation.
If the kernel does not link at the end of installation, try to boot from the kernel called /stand/unix.safe (which does not contain the third-party drivers) into single-user mode.
If the driver for the root hard disk controller is
one of the third-party drivers missing,
the unix.safe kernel will not boot.
If this happens, boot the system using
a Boot-Time Loadable Driver (BTLD) for this
SCO OpenServer system.
Then, remove the old driver from the link kit, and
install the BTLD using