How use Excel and Word files with a computer that doesn't have both?

[iQChange]

I have to develop an application that uses Qt, Excel and live-time file checking. My client gave me this:

I have a problem at work. I need you to develop this:
I want one application with GUI (it said windows), that generates an report for each sheet (employee name) in the file, with the colums. I don't want to make the computer slower, so check the file and get the name of the employee that is altered and only change his report

I have no idea how to start it. All Excel libraries I use stop working on my computer and this "File Checking" is other trouble, because if for each second I compare the size of the "old" file with "new" file, the memory will explode. What should I do?

[MiiNiPaa]

Define "Excel file". CSV files have elementary structure and are easy to create. RTF files have simple structure too and can be opened with Word.

[iQChange]

.xlsx

[MiiNiPaa]

Good luck with parsing one of the most complex file formats. Basically it is a zip archive with a bunch of XML files inside. So you will need at least XML library to handle it. Documentation on Office Open XMP is hard to find, but these links might help you.
http://msdn.microsoft.com/en-us/library/dd922181%28v=office.12%29.aspx
https://en.wikipedia.org/wiki/Office_Open_XML_file_formats

[kbw]

Tried Goggle Drive?

[iQChange]

@kbw

Tried Google Drive?

How can GDrive help me?
My biggest problem now is checking the file... Any ideas?