Cursor in excel does not work

I use Window 7 and Office 2010 with license. I bought in Bangkok, Thailand. This morning my cursor in excel has been changed from arrow to be thick white cross. The cross can be move but it cannot move any cell or drag the formular.
I called Microsoft Service Center for help. As advised by Microsoft, I have uninstalled Office 2010 and reinstalled, but the cursor in Excel is not changed, it still be a thick white cross.

Please help me.
Thanks & Regards,
MooPhet