Update:

I've noticed that when I scroll through the entire list of members when all members are on show, then change to "online only" I can see everyone who is online. So it looks like it's some kind of caching issue with Oxwall.

it's a oxwall 1.7 problem, they're working on it

Kev, can you please try to reproduce that on demo? Also we would like if you provide us with the steps how we can reproduce that on our websites. 

The update with the fixes for mailbox plugin is now in the store it should show up in your admin panel within next 24 hours. 

Thanks Ross,

So do you still need me to try and replicate it on the demo?

Do you have that issue even after updating the plugin?

Nope, seems to be working fine now. Thanks for the quick fix!

Alright, I'm going to mark this post as Solved then. 

I'm getting this issue on 1.7.2 and just have a Messages plugin, not a Mailbox one.

Rob, what is your Mailbox plugin version? you can check that in ow_plugins/mailbox/plugin.xml file the build is indicated there. 

So that an online user appear in chat you must have a conversation with that user previously or be friends with him/her. If all that is met, please check whether your cron job is properly configured. There are a lot of posts related to the cron issue. Please follow this link: http://www.oxwall.org/forum/section/2/search?&q=cron%20is%20not%20working and check the solutions in posts. 

Topic was moved from Installation Troubleshooter and Server setup.

Mailbox plugin is 8524 according to the XML file. And I see lots of people in chat who I'm not friends with. In addition, chat message notifications remain permanently (as in right now I have 6 notifications that never go away, because 6 people have chatted to me instead of PMed me).

I installed Oxwall via Softaculous on my host rather than manually, so didn't set up the Cron job. I don't see an error file in the ow_cron folder (just run.php). I just manually ran Cron and it did fix the number of users online (good), so I guess cron isn't working (bad), but it didn't fix the number of notifications I've got for Chat messages.

I'm afraid I know nothing about cron jobs, but I had a look at the cron job script in CPanel and it looked like it was confused between my main account domain and my addon domain where I have Oxwall installed.

I changed it to read as below and I guess I now just wait to see if it fires automatically:

*****wget -q -O /dev/null http://www.mywebsite.com/o/ow_cron/run.php

Rob, please make sure that all those chat messages are read. Go to the bottom of the conversations list. Also you can use the bulk option here: www.site.com/messages and mark all chat conversations or all your conversations including PM as read

As to the cron, please check this tutorial: https://docs.oxwall.org/install:cron to configure your cron jobs properly

Cron looks like it's configured correctly according to that document. I'm guessing my host (A Small Orange) allows wget CronJobs since it's set up via the CPanel they've given me.

As for chat notifications: I've tried everything. Bulk marking as read included. If I go to /messages/ then all of the things with a mail icon work fine. All of the things with chat bubble icons seem to remain as notifications no matter what I do.