Cursor is not blinking....
 

I am usuing Debian 5.0.2 Lenny. Recently, I installed some softwares in my linux box. I have no clue why cursors are not blinking anymore in some programs.

cursors are blinking fine in: Iceweasel, gnome-terminal, gvim and more....
cursors are not blinking and not visible: gedit,thunar

I have noticed that cursors are blinking when I run gedit and thuna as root. Cursors are not blinking and not visible when I use text input box in most of programs. Cursors are not blinking in all text input boxes in programs basic programs under the menue System->Preferences and System-> Administration.

wow, sounds like a pretty serious problem you have there ;)

install gconf-editor if you don't have it and edit desktop->gnome->interface->blinking_cursor

I have this same problem, and "cursor_blink" was already checked in gconf-editor. Unchecking and checking again, however, seems to have helped, although not immediately (after about 1-2 minutes), so I'm not certain it was this that fixed the problem.

If you are still using debian like the OP then you are running an unsupported version & need to update to the current edition which is wheezy.
Also you need to open a new thread so that you can get the help you need.