There is a known issue, where attempting to perform a DataSocket Open on a disconnected OPC server causes the LabVIEW interface to freeze. This issue has been known since at least LV6.0 (2002 forum post) and has continued to be an issue over the years (2007 forum post, 2011 forum post). I recently tested it out in LV2018 and found that the issue remains unresolved. Is this still on the 'to-do' list as an open Corrective Action Request or should we assume that the issue will remain for the foreseeable future? Has anyone found a workaround that does not require DSC?
