XF 1.5 Phantom PM

[Vigilance]

In my PM box, it keeps ticking a conversation as unread even though I've opened the PM multiple times. The PM notification is shown on the index page as well. Even ticking the "mark conversation as unread" and then unticking it doesn't help.

Looking forward to any advice.
Cheers.

 

[Vigilance]

Any help for this?

 

[Vigilance]

Please?

Now I have 3 Phantom PMs. NO similarities in any of them (conversation locked or anything etc)

 

[M@rc]

1. Do you have any type of server-side caching enabled?
2. Does it happen with all add-ons disabled and on the default XF theme?