The FIMS user needs to change the following setting to "Yes" in FIMS:
  • Click "Tools" > User Preferences.
  • Click "OK"
  • Under the middle column (Option), scroll down and select "Use_MAPI_Always_Enabled".
  • Under the right column (Value), select "Yes"
  • Click OK.
Now the Send message button should display on the report in question.