Problems sending mail after traveler upgrade

I recently upgraded a client’s server from Traveler 901.07 to the most recent version 901.21

Since the upgrade, none of the users can send mail from their devices.

The error in the log is "Traveler: SEVERE User Name An exception occurred while writing data into database http://Traveler Server/mail.2Funame.nsf http://email.capebretonrealty.com/mail.2Fvcarter.nsf. Exception information: Exception Thrown: com.lotus.sync.dca.CAException:

A web search returns no information on this error. This was not a problem before the upgrade and I can find no security errors. I have tried disabling the Run As User feature to no-avail.

Any thoughts on how to determine the root cause of this? (I note that the url that is being created is an http rather than https, but all of the devices are set to use https for the url.)

Subject: Trusted server

Add Traveler server as Trusted server in Mail server Configuration document on Security tab

Subject: downgrade

Thanks. I had already reviewed the security settings contained in a ibm technote about a similar problem. This was a server that had been running Traveler for at least 6 years, and had already had all of these settings correct. I tried numerous fixes including resetting * users to no avail. In the end, I uninstalled Traveler upgraded just to the ,20 version and then reset all of the users again. That seems to have resolved the issue. I will try the .21 upgrade for another client this week and see if the problem is was a one off or related to the .21 code.