I have seen some users of the Outlook client be pestered by pop-ups every time they open any CRM window from within Outlook. The message they get is:
One fix that was found for this issue is to go to the Internet Option Settings in Internet Explorer and turn "Protected Mode" OFF on the INTERNET ZONE under the Security tab. You will be warned that your computer will be at risk of getting something bad the easies solution to that is responsible web browsing. For whatever reason doing this on the Intranet or Trusted Sites zones didn't fix the problem (even though the CRM site was put in each zone).
Perhaps there are other better ways out there but this is one that works.
Dynamic Methods Inc.