Hi,
As mentioned, you should check the logs to identify what's causing the issue. Check on both initiator (Windows Server) and target sides.
As an alternative, you can automate the connection process and use PowerShell to connect to iSCSI target on a certain event. The following article might help:
https://www.starwindsoftware.com/blog/dont-break-your-fingers-with-hundreds-of-clicks-automate-windows-iscsi-connections
Cheers,
Alex Bykovskyi
StarWind Software
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