UPS not working

[Ramsnet]

My UPS doesn't seem to work. I experienced a blackout earlier this day and the UPS doesn't keep turning on. My UPS is a Prolink PRO1200S. My PC with 850W power supply and a 19" LG monitor is the only thing that is drawing power. I'm using a power strip (not a surge strip) to connect the PC and the monitor to the UPS. I don't know if that's causing the problem, or a faulty UPS. The lights on the UPS itself indicate "charge" and "normal" in yellow.
Please help.

 

[misteriosly]

Charge and normal in yellow ? Can you give a screenshot ?
According to http://www.prolink2u.com/download/um/um_PRO.Series.UPS_ver5.2_16.07.2010.pdf
You have yellow green and red, cant see two yellow ?