We recently upgraded to CommuniGate Pro version 5.3.10, which includes MAPI component 1.53.10.1, and Outlook now crashes when I send a message that includes an attachment. And given that the message remains in the outbox, all subsequent restarts of Outlook also result in a crash. What is the problem?

Unfortunately the MAPI component 1.53.10.1 has a bug that causes these crashes while sending messages over SSL/TLS. The workaround is to disable SSL in the account settings, or install on the server the version 1.53.10.2 that provides the fix: manually put the cgmxp32.dll from /ftp.communigate.com/pub/client/CGPro-MAPIserv-Intel-1.53.10.2.zip> into the Services directory of the CGP application directory (e.g. /opt/CommuniGate/Services on Linux or Solaris) and then press the Refresh button on the 'Settings | General | Info' page of the CGP web administration interface.