There is no need to automate Word, which is rather slow and brittle due to pop-up messages, or to use Microsoft's Office File Converter (ofc.exe), which has an unnecessarily complicated user interface.
The simplest and fastest way would be to install either Office 2007 or download and install the Compatibility Pack from Microsoft (if not already done). Then you can convert from .doc to .docx easily using the following command:
"C:\Program Files\Microsoft Office\Office12\wordconv.exe" -oice -nme <input file> <output file>
where <input file> and <output file> need to be fully qualified path names.
The command can be easily applied to multiple documents using for:
for %F in (*.doc) do "C:\Program Files\Microsoft Office\Office12\wordconv.exe" -oice -nme "%F" "%Fx"
The easiest way is to use the command-line Office File Converter. Just run
ofc
and the magic happens.
Automate Word.
If you are using .NET, add Microsoft.Office.Interop.Word (make sure it is version 12 - equivalent to Word 2007 so you can achieve the above) reference assembly to your project and use it it automate word app to do exactly what you want to do above. The pseudocode
You can find plenty of example on google, just search for Word Automation in C# or something along that line.
