subscription-manager-gui cannot be displayed

Hi there, I'm trying to lunch subscription-manager-gui via X client on my widnows 7 laptop (Win 7+ Putty+Xming, X11 forward checked), the problem is, the gui shows up only one time, then later for some reason I clsoed the gui by click "clsoe" - I think I did that, and then I found the Putty terminal session seems hang, so I just closed putty and quit the session. After that, when I re-open putty and try to lunch the subscription-manager-gui . it never shows again. - at the same time, I can lunch netca gui or dbca gui without any problem.

Can somebody help on this? Thanks!