We're seeing some issues with connecting to the existing Oracle 11gR1 database. We've got a couple of work-arounds that will get us through to the completed upgrade to Oracle 12c.

1) The DBA team is returning the 11gR1 database to "Read/Write" mode as opposed to "Read Only." This should enable connectivity with the ArcGIS Desktop 10.3.1 client. 

However, please note: ANY DATA YOU ADD TO THE 11gR1 DATABASE WILL BE LOST IN THE TRANSITION TO 12C. So please don't add any data to the database, use it only as "read."

2) We're seeing some success using the ArcGIS Desktop 10.5 client to connect to the 11gR1 database. If you haven't previously updated to ArcGIS Desktop 10.5 please make a request to your service unit for an upgrade. We're planning a full rollout of the 10.5 Desktop client but hadn't been pushing for it until after the upgrade to ArcGIS 10.5 on server. 

Thanks for your continued patience as we go through a few final quirks before the upgrade to Oracle 12c and ArcGIS 10.5 is complete.

Butch Lazorchak
IT Project Manager
Geospatial Hosting Environment project
ServiceNow Implementation project
Library of Congress
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