Problem with one page checkout

[Moii]

Hello, I need help.

I updated joomla and virtuemart to the newest version. Then I turned on SEF. Now I have a problem and I dont know where is it.
My webshop is old for about a year and till now I didnt have this problem.

When the shop was made I bought one page checkout plugin and it all worked ok.

Now I made an update for joomla and VM and when buyer clicks "order" a window is opened and there says "add to cart". when you click "add to cart" instead of opening one page checkout it says that there is no item in the cart.

It doesnt show always. Sometime buyer can buy item without a problem and sometimes the problem occurs. It is not good for my business so I was wondering does anybody know where should be the problem?

Please help

[jenkinhill]

You may need an update for your OPC. See http://forum.virtuemart.net/index.php?topic=120943.msg412515#msg412515

[Moii]

yes I also think so but there is a problem. I bought OPC not directly. The company that made my webshop bought it for me. I just payed for it.
I m not in contact with them so I dont know how to do it now.

I have another joomla developer and he also said that he thinks that it should be updated but I was wondering how because I didnt buy it directly.

Any thoughts about how to do it now?

[jenkinhill]

You will need to contact the OPC supplier and explain what happened. Maybe they will help. We cannot provide update support for commercial plugins.

[Moii]

yes, I have already send them an email so I m waiting for response.

thank you

[Moii]

yes I also think so but there is a problem. I bought OPC not directly. The company that made my webshop bought it for me. I just payed for it.
I m not in contact with them so I dont know how to do it now.

I have another joomla developer and he also said that he thinks that it should be updated but I was wondering how because I didnt buy it directly.

Any thoughts about how to do it now?

I just read this link you gave me. can you tell me where can I find that file that has to be changed?