X2 jammed. After reboot, extra bracket sign appears in all repeated citations

Greetings everybody,
I am new to EndNote Discourse.
I use EndNote X2 with Word 2007. My OS is Windows 7 Professional.
Whenever I leave X2 turned on for more than 3 hrs or so, it jams–a note appears in X2 saying “EndNote is not responding” or something like that. I cannot close EndNote even if I want to: all keys are un-responsive. I have to close everything on my computer (except EndNote which I could not close), power off my computer, then power back on. Usually, when I power back on, I turn on EndNote X2 and it works fine.
But, a couple of days ago, X2 was jammed again, I powered off the computerr and powered back on, and when I turned X2 back on, all citations work normal except repeated citations: an extra close-bracket sign appears in the citation. E.g., in a consecutive footnote, instead of Ibid., 15, the citation becomes Ibid.), 15. E.g., in a repeated but non-consecutive footnote, instead of Harding, Wildlife, 102, the citation becomes Harding, Wildlife), 102.
I checked Instant Formatting, and it is turned on.
I am unable to fix the corrupted formating for repeated citations. Please help.