can't close IE using the X

HI I am searching for the answer for a dear elderly friend in Hawaii that I know.
she asked me tonight if I knew what she may have done to cause IE to not close normally she has been shutting down her computer completely to close it until I explained the crtl alt del function and how to use it instead but I told her I would check around to find out what might be wrong.

It will not close when she clicks on the X nor can she get it to close by clicking on it in the taskbar and going to close.

I don't use IE much I prefer to use Firefox myself ..but because she is a sweetheart and we have been friends online for almost 10 years she feels comfortable in asking me questions about computers as she knows I will find answers that I do not already know and explain them so she understands.

Help????