I have a strange situation where two users of Spark 2.5.8 can successfully communicate with with most other openfire users but when one user tries to open a chat the target users Spark hits high CPU and he has to use task manager to exit the app.

However if the traget user mentioned above open a chat with the same user that caused the issue everything is fine.

As I said this only happens with this two users and the issue is just one way.

We have removed all traces of the client from both machines but the issue still remains......

Any ideas?