DOC file doesn't load

DOC file doesn't load

I am a new user and I loaded some word documents to test zoho docs. The word documents are small files (69-88 kb)After clicking on them, either to view or to edit, it comes to the window that says:
"The preview of this document is being generated. It will be available after few minutes."
After several minutes it never loads. So I cannot view or edit within ZOHO docs. What is the problem? I uploaded a pdf considerably larger, it opens after a few seconds. The DOC files are available to dowload but will not open up in browser. I am using Internet Explorer
Any help will be appreciated.