iDrac 6 upgrade to 2.80

hi everybody

I've just upgraded my iDrac Enterprise to 2.80 using windows 
package on Windows and now when I try to log in using GUI it 
kind of logs me in but next second it logs out and I see 
login screen again.
These are R815 I'm about to upgrade (this one is Win but the 
rest are Linux) and I wonder if anybody has experience this 
problem?
If this is a serious problem? if is then I'd rather not 
upgrade I guess.

many thanks.
L.