[CentOS] users unable to log into kde after 6.8 update

greetings to all.

centos = 6.8 current system = toshiba l455d-s5976 laptop

a new problem has developed after 1st updating of 6.8.

regular user is not able to open kde desktop, can open gnome desktop.

root user can open either kde or gnome desktop.

as a user, when i try to open kde, after entering password, screen goes to a solid blue, then shows a quick full screen view of command line text, too quick to read, then screen changes back to login prompt.

logged in as root, i created a second user, still have same results as above.

searching thru 2+ years of local archives revealed nothing, nor does web searching.

any advise, recommendation, suggestion appreciated.

tia.