The Offline Client is important for preparing for outages.
To download the Offline Client you need to make sure that you have a current, relevant WMS NCIP Service WSKey.
To do this:
If you are still unable to download the Offline Client, contact OCLC Support
Note that there is a known issue with Java updates later than 8.162 that makes the Offline Client unable to be run from the start menu
https://help-nl.oclc.org/Library_Management/WorldShare_Circulation/Release_notes_and_known_issues/Known_issues
The known workarounds to this are:
1. Install Java SE Runtime Environment 8u162 or earlier to run the Offline Client application from your workstation's Start Menu.
2. If running a later version of Java 8, you can still run the applications by executing the JNLP files directly (i.e. wms-offline-circulation.jnlp)
Note that Java 9 or later is not supported.
Links
Preparing for an outages
Preventing WSKeys from expiring