OMERO connection on Windows

I cannot manage to open a connection to OMERO from windows. This is the output on my linux machine and the windows version (also python 3.8.5) conn.connect() returns false.

import sys
'3.8.5 (default, Sep  7 2020, 13:24:44) \n[GCC 9.3.1 20200408 (Red Hat 9.3.1-2)]'
from omero.gateway import BlitzGateway
conn = BlitzGateway(username='user_name',
...                     passwd='fake_password',
...                     host='',
...                     port=4064,
...                     group='group_name')

The two computers are in the same network. OMERO insight is working fine on the windows machine.
Is there any test I can do to check things further?
I went through this topic but it does not seem that the issue is fixed…

I’ve tested this in a Windows 2012 Vagrant VM with the omero-py 5.8.2 conda package:

conda create -n omero-20201008 -y -c ome omero-py ipython
conda activate omero-20201008
conda install -y pywin32

and it’s working for me, I connected to Note pywin32 should be automatically installed on Windows but it’s not for unknown reasons:

Could you give us more details of your Windows setup? Can you try connecting to so we can focus on your Windows client configuration without worrying about any server customisations for now?

Ok. It seems to be server and OS related.
Our production server is version 5.5 and while I’m running the latest omero-py version on my linux machine, everything seems to be working fine. At least I can connect to it and I dind’t notice any issue. But not on windows. Connecting to the demo server from windows is working fine.
I guess it’s time to do the server upgrade.
Thanks and sorry for the hassle. I should have checked with the demo server. It just didn’t cross my mind that the behavior would be different.
Best, Julio

There are several tweaks to the IceSSL settings in the latest releases. Each operating system imposes different restrictions on the allowed SSL transport and ciphers settings, and it it also varies between Python and Java. We’ve tried to adjust the built-in OMERO IceSSL configuration to deal with this.

It’s also worth noting that BlitzGateway.connect() hides any error messages, in future it may help to use

client = omero.client(HOST)
session = client.createSession(USERNAME, PASSWORD)

to investigate connection problems.