Users can't check out; billin address not saved

[MunchyBugs]

We were using Joomla 2.5.6 and VM2.0.10.  The site was working fine.  Then just today users get stuck in a loop when trying to check out.  After the cart when they proceed to check out either by the "Check out" button or via the "add billing address" button they are taken to the billing address entry form.  After you fill this out and click save it simply refreshes the page except all the fields are blank.  You can do this as many times as you want but it doesn't work.  I upgraded to VM2.0.20b and have the same problem.  I've searched high and low for a solution but can't find one.  We had to take our site offline and redirect people to another place where they can buy tickets for an upcoming event.  We are a small non-profit so any help would be appreciated.  I've checked with all admins and no one has messed with or changed anything that would relate to this.  Also, I should mention that we are not using a login.  People have not needed an account or needed to be logged in to comment.

The site is http://www.moenviron.org if you are interested in seeing the problem. 

Thanks,
Eric.

[flow23]

Hi,

I have some knowledge in Virtuemart, could I get an backend access to see if I can help you with the issue, I went to your site and looks like that issue could be easily fix just want to check if it can be fixed through the backend if not possible then we should get more help with the coding.

[jenkinhill]

Same issue as in this thread:  http://forum.virtuemart.net/index.php?topic=114764.0

Most likely you need to disable Rokbox.

[MunchyBugs]

Thanks for all yer help!  The problem was indeed RokBox but you don't need to diable it.  What worked for me was going into the two rokbox plugin's settings and setting Backwards Compatibility to DISABLED.  Default is ENABLED and this causes the problems.  Weird, I know.