The XPS Viewer is the newest IRM aware viewer. XPS is essentially to Microsoft, what PDFs are to Adobe, but cooler.
You can essentially print 'anything' out to the XPS writer, and then RMS protect that content. So if you have a PDF, or a CAD design, NewEgg receipt or pretty much anything that you can send to a printer, you can RMS protect that, and people with rights in the publishing license will be able to open it, just like they would a PDF file, and just like the PDF viewers, this is a viewer meaning you can't modify the doc.
There are some things to note:
On XP you need to install the .Net Framework 3.0. On Vista, you also need to install the following hotfix http://support.microsoft.com/?id=932471, the fix is also available for XP, but you have to update your XPSP2 machine through the Windows Update center. The fix will be available for XP on the download center soon.
See this link for the downloads for the document writer:
If you are outside of the domain (i.e. on the internet), and you need the XPS viewer to know where your RMS installation is you need to set some registry overrides.
Set the default value to http://url.to.rms.server/_wmcs/certification
Set the default value to http://url.to.rms.server/_wmcs/licensing
Welcome to the world of the newest, slick, RMS aware viewer.
If you are on Vista, and getting an error message that resembles the following:
"Cannot open this document because your permissions have expired"
Make this modification in the registry to correct the issue (yes, this is a bug).
Key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\Windows Presentation Foundation\Hosting
Also check out the following KB: