I updated both the Windows 10 client and the Ubuntu 16.04 server to the very latest releases and the problem has disappeared.

Thank you for your help.  My server may have been a little too old for the new client version I was using.

-----Original Message-----
From: X2Go Bug Tracking System <owner@bugs.x2go.org>
To: krehberg <krehberg@aol.com>
Sent: Fri, Mar 9, 2018 2:15 pm
Subject: Bug#1269: Acknowledgement (X2go server crashes on Ubuntu 16.04 starting at 2018-03-08)

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1269: http://bugs.x2go.org/cgi-bin/bugreport.cgi?bug=1269
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