Instant message conversation cannot be initiated from some users

Hello,

this issue happened to me last week (I am on 8.5.2) and now it happened to a colleague on 7.0.3:

When I try to chat with someone using the embedded sametime client, it works perfectly: a window opens on his side with what I wrote.

When the same user tries to chat with me, no window opens and I do not receive what he wrote until I open a conversation with him.

So I could initiate conversatiosn but not all users could initiate some with me.

I was still trying to find a fix and showing a colleague when it suddenly worked again. Naturally, I did not bother anymore, especially as I was not able to reproduce the error.

Now this other colleage is experiencing the same problems, however on his side the issue did not resolve itself and in the meantime the whole server was restarted (so this could not be the reason…)

Any ideas or anybody who experienced the same?

Hints are most welcome!

Cheers!