Important Information about the LetterMark Previewer Error

On August 11th, 2009, Microsoft released a series of security fixes for Windows that break backwards compatibility for applications such as the LetterMark software.

This update results in the following error message when sending emails after the updates been applied:

There was an error displaying the LetterMark preview window. Do you want to send the e-mail without LetterMark?

Please see our Knowledge Base article, #1442 for solutions and workarounds to this problem.