RFA Java does not use Windows registry direclty, but Java preferences API to manage the configuration. Since you mention that your application is multi-threaded, so I suppose it is some kind of race around condition. Try adding pause within your application to see if any thread is trying to access login state/data before its available.

@tonyny2016,

You will have to provide more details. Is this a new application? Can you reproduce the exception with RFAJ samples - like QuickStartConsumer provided with the SDK?

We are migrating to RFAJ 8, and existing program is multi-threaded, so after start, there are multiple threads concurrently trying to connect to the service, and sometimes we got this exception. It's hard to reproduce this scenario but I feel it may related to login stage, when wait for response event and waiting time is too short. Anything wrong with Windows Registry usage?QuickStartConsumer works fine.

@Gurpreet We are migrating to RFAJ 8, and existing program is multi-threaded, so after start, there are multiple threads concurrently trying to connect to the service, and sometimes we got this exception. It's hard to reproduce this scenario but I feel it may related to login stage, when wait for response event and waiting time is too short. Anything wrong with Windows Registry usage?QuickStartConsumer works fine.

@Gurpreet Ok, I will try the suggested approach, thank you!