However, I stumbled upon a quick and easy work around and this is how it works (You will need to use Internet Explorer browser for this fix to work):
Step one - Open a Microsoft live or Hotmail account if you don't already have one. If you do log in.
Step two - On the top menu, hover your mouse on "Office" and then click on "your documents" as shown in the screen capture below.
Step three - Next, navigate to "Add files" as shown below. Select the corrupted .docx file from the location on your computer and upload it to Office docs.
Step four - Go to "My Documents" and click on "Edit in Browser" as shown in the screen capture below.
Step five - The .docx file will open in the browser. Kindly note that this is the reason you need to use Internet Explorer. This feature does not work in Mozilla or Chrome.
This fix has worked wonderfully for me on two occasions when large documents which both had a table of contents got corrupted. I was able to recover them using this method in less than five minutes. For some reason, the documents can be opened online but cannot open locally on your computer. There appears to be a bug in MS Word 2007 (.docx) which the guys at Microsoft do not want to admit to. All other fixes recommended on their website DO NOT work. I am not sure if the same fix works with Google Docs, I suspect it might though there is the limitation that you can only upload documents up to 1mb which is quite limiting if you work with large documents. Microsoft Office Live Workspace is one of the best online backup service and allows you to upload a document as large as 25MB.
I will post an update once I test this fix on Google Docs for small documents of less than 1MB ... or you can try it out yourself and post a comment back here letting us know if it works.
See Part II of this fix or try Free Word Recovery Software.