We have an application that is used by over 8000 people worldwide. One of our users is just starting to have the following problem:
Run-time error '-2147467259(80004005)':
Method 'Add' of object 'CommandBarControls' failed

I have read that this problem can be caused by trying to open the file in Internet Explorer. The user has told me that she has tried opening MS Excel and then the .xls file and she still gets the same problem when the file is trying to open. She is the only one that has had this problem. Could there be something wrong with her Excel settings or some sort of Internet Explorer settings?