User Logged out and blank confirmation page after come back from ipay88 payment

Hi,

First, I would recommend that you activate temporarily the "error reporting" and "debug mode" settings of the Joomla configuration and do a test again. That should hopefully display some error message on that white page, explaining what is the cause of the problem.
That's really important to provide a solution.

Second, I would recommend that you try again with another payment plugin, like "collect on delivery" so that you can create a test order without paying anything, and confirm manually the order. If everything works fine with it, it would likely mean that the issue is relative to the payment plugin, like you guessed. Otherwise, it means that the problem is likely not in the payment plugin but something else and the first point with the debug information will be crutial in understanding what's going on.

Finally, supposing that the problem you have comes from this plugin, please note that this ipay88 plugin is developed by Dreamztech. So if a problem is found in the plugin, it's really important to contact them so that they can help you and if something needs to be fixed, implement the modification in the plugin so that anyone else won't have the problem in the future. So please make sure you send them a message:
www.dreamztech.com.my/contact
I'll also send them a link to this thread so that they can look into it.

Hello,

It seems that you didn't use this plugin version ( here ) but another one, or maybe this very old version ( here ), and if yes, there are good chance that this explain why the plugin crash after you have updated for a more recent HikaShop version.

The only thing that we can tell you now, is to use this plugin version or another payment platform & plugin ?...
Hope this will you to progress on your solution.

Regards