Not able to select

hi

i have DS2025 SP0 x 64. 

it was all working fine but don't know what happened yesterday, i am not able to select anything in drawing. either same or any other file or even new.

 

when i click and try to select something, i am not able to get the rectangle or square shape of my selected size, rather i get some weird profile.

 

can someone pls help as i am stuck now.