[SOLVED] J4 / VM4 - Impossible to Complete Orders with Coupon Code

[ml12]

Hello everyone,

I am currently building my shop website and everything has been working smoothly so far but I am encountering a problem that I have not been able to solve yet and I didn't find a topic covering this.

When I want to complete an order using a coupon code (either 100% or less), I get an error message saying :

An error has occurred during the execution of the request.

You may not be able to visit this page due to:

• an outdated link/bookmark
• an incorrect url
• a search engine has an outdated listing for this site
• you do not have access to this page

If difficulties persist, please contact the administrator of this site and report the errors below.

0 Call to undefined method Joomla\Database\Mysqli\MysqliDriver::query()

However, I tried to complete an order without coupon code and it works fine this way.

I am using Joomla 4 with Virtuemart 4.0.0 and all my products are digital ones working with the "digital products shipment" extension.

Does anyone have an idea where this might come from and how to resolve this problem?

I am wondering if this is not a problem with some code that is not functional with Joomla 4?

I would be very very grateful for any help or advice. Thank you

Wishing you all the best,
Mathias

[GJC Web Design]

you need to provide the trace...  https://forum.virtuemart.net/index.php?topic=117042.0

[ml12]

Hello,

Thank you for your answer and help.

Unfortunately, I wasn't able to have more details regarding the error I encountered with Joomla and VM debug mode or by making changes to some files to display it, not even in the server log files. Nothing showed up.

It only showed an issue around 'query()' which seems, after having done some research, to be a known problem with Joomla 4. So I decided to downgrade the site to Joomla 3.9 and it works perfectly now.

I wish you all the best and a beautiful day.

Kind Regards,
Mathias