1. Install Wine via Software Center, Synaptic Package Manager or via the command line:
$ sudo apt-get install wine
2. Download winetricks:
$ wget http://www.kegel.com/wine/winetricks
3. Now install winetricks and other packages:
$ sh winetricks msxml6 gdiplus gecko vcrun2005 ie6
4. Configure Wine by navigating to Applications –> Wine –> Configure Wine, and then set “Windows Version” to Windows Vista inside the Applications tab.
5. From the “Libraries” tab, look for rpcrt4.dll and msxml3.dll and add them to “Existing overrides”. Edit Existing overrides and make sure the load order is set to “Native (Windows)”.
6. Download rpcrt4.dll (.zip) from HERE, and then extract it.
7. From the Wine menu, browse C:\ drive and navigate to windows/system32 directory. Copy the downloaded rpcrt4.dll inside system32 to overwrite or replace the existing rpcrt4.dll.
8. Put Microsoft Office installer, click on setup, and just follow the normal installation process.
9. After installing MS Office, configure Wine again and set Windows version back to Windows XP.
10. You can now use MS Office inside Ubuntu Linux by navigating to Applications –> Programs –> Microsoft Office.