Hope this is the correct place to be posting this... if not plz redirct me!

 

I am trying to open a file and getting the below message. Is there something that can be done to fix it? Hope so it is my tax summary for this year and will be a pain in the *** to have collate all the data!

 

The document “INVOICES 2012-13” is invalid.
The index.xml file is missing.

 

Cheers