Signals Image Artist: SImA Loader connection error when attempting to upload or download data

When attempting to download (or upload) data via the SImA Loader, the following error can be seen in the SImA Loader log:

"Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ConnectTimeoutError(<urllib3.connection.HTTPSConnection object at 0x000001C7D6909CD0>, 'Connection to sima_host timed out. (connect timeout=None)')'

Where sima_host is either the hostname or IP address of the SImA server.

Check to make sure that the appropriate firewall rules and exceptions have been made. In SImA 1.3 or above it is a requirement for the firewall between client computers and the Signals Image Artist server to allow TCP traffic on port 9500 (assuming SImA is NOT using S3 storage, where this isn't a requirement).