Hi,
Riched20.dll is part of the operating system that is causing MSN to Crash.
First, follow the steps to reset Internet Explorer which is the back bone of MSN: http://support.microsoft.com/kb/923737
If the same issue persists, follow the steps on this link to create a new User Profile: http://windows.microsoft.com/en-US/windows-vista/Fix-a-corrupted-user-profile
You may then switch Users and log in to the new Profile and check if you can sign in on MSN.
Once the issue is resolved, contact your computer manufacturer so that all your files can be transferred from the old profile to the new one.
If the computer is out of warranty, you may also contact our Product Support Specialists. Please check the Private Message area below for contact details.
For the laptop computer, try these following step at the private message area.
Thanks,
Paolo M.